The ODBC standard defines four connection attributes:
DSN
Driver
UID
PWD
For a description of the ODBC definition of these attributes, see the appropriate ODBC manual for your platform:
Microsoft ODBC 3.0 Programmer's Reference and SDK Guide
Microsoft ODBC 2.0 Programmer's Reference and SDK Guide
This chapter describes all the connection attributes defined by TimesTen. To view the names and values of most attributes specified in the connection string, an application can use the ttConfiguration
built-in procedure.
Note:
According to the ODBC standard, when an attribute occurs multiple times in a connection string, the first value specified is used, not the last value.On Windows, False
means the check box is unchecked and True
means the check box is checked.
On UNIX and Linux systems, False
means the attribute value is set to 0
and True
means the attribute value is set to 1
.
The following sections provide details on all TimesTen attributes, which are first listed in tables in "List of attributes". Following the tables, this chapter describes each attribute in detail.
Only the instance administrator can change a first connection attribute to a value other than the one currently in effect. (No privileges are required to change AutoCreate
and ForceConnect
.)
This section includes the tables:
Table 2-1 Data store attributes
Name | Description | Default |
---|---|---|
A name that identifies the specific attributes of a connection to the database. |
None |
|
Identifies the physical database. |
None |
|
Identifies the character set used by the database. This attribute is required at database creation time. |
None |
|
A statement that identifies the use of the data source name. |
None |
|
Specifies the TimesTen ODBC Driver Manager. |
None |
|
Determines the durability of "prepare-to-commit" and commit records |
If K-safety is set to If K-safety is set to |
|
The directory where transaction log files are stored. |
None |
|
Specifies that disk space for the checkpoint files should be preallocated when creating the database. |
1 (True) |
|
Enables automatic parallel replication. |
|
|
Specifies the number of tracks available for automatic parallel replication. |
4 |
|
Specifies that the database is not saved to disk. |
|
Table 2-2 First connection attributes
Name | Description | Default |
---|---|---|
Specifies that the first connection creates the database if it does not exist. |
|
|
Controls the number of log files that can accumulate before a backup fails. |
|
|
Controls the frequency in seconds that TimesTen performs a background checkpoint. |
|
|
Controls the amount of data in megabytes that collects in the log between background checkpoints. |
The value of the |
|
Controls the maximum rate at which data should be written to disk during a checkpoint operation. |
|
|
Controls the number of threads used to read a checkpoint file when loading the database into memory. |
|
|
Indicates the upper bound on the number of user-specified concurrent connections to the database. |
The lesser of |
|
Indicates the number of seconds between epochs. |
If Durability = 1, the default is 0. (System does not generate periodic epochs) If Durability = 0, the default is 1. |
|
Specifies whether a connection is allowed to a failed database if it is not properly restored from the corresponding subscriber database. |
|
|
Enables forced disconnections through |
|
|
Determines whether the first connection to a database should proceed if TimesTen recovery encounters a defective log record. |
|
|
The size of the internal log buffer in MB. |
|
|
The number of log buffer strands. |
|
|
The transaction log file size in MB. |
The value of the |
|
Controls the method used by TimesTen to write and sync log data to transaction log files. |
|
|
Specifies that unneeded transaction log files are deleted during a checkpoint operation. |
|
|
enables applications that connect to a shared database to specify whether the real memory should be locked during database loading. |
|
|
Specifies that the existing database should be overwritten with a new one when a connection is attempted. |
|
|
The size in MB for the permanent partition of the database. |
|
|
The number of threads used to rebuild indexes during recovery. |
4 |
|
The size in MB for the temporary partition of the database. |
The default size as determined from the |
Table 2-3 General connection attributes
Name | Description | Default |
---|---|---|
Specifies the time limit to wait for a channel create request to complete. |
30,000 milliseconds |
|
Specifies the maximum size of the commit buffer in the transaction control block. |
16 KB |
|
Specifies whether there is a symbolic name for the data source. |
The process name. |
|
Specifies if each commit generates an epoch. |
|
|
Determines whether a table or sequence is included in an active standby pair replication scheme when it is created, which can only occur if the |
|
|
Enables replication of data definition language (DDL) statements in an active standby replication scheme. |
|
|
Specifies whether diagnostic messages are generated. |
|
|
Specifies that commit operations should write log records to disk. |
|
|
Specifies which parts of shared memory are included in a core dump. |
0 (None) |
|
Specifies whether the isolation level is read committed or serializable. |
|
|
Specifies whether the connection should use row-level locking (value = 0) or database-level locking (value = 1). |
|
|
Enables an application to configure the lock wait interval for the connection. |
|
|
Sets optimizer hints at the connection level. |
None |
|
The threshold at which TimesTen returns a warning when the permanent partition of the database is low in memory. |
90% |
|
Determines if commands are shared between connections. |
|
|
See "UID and PWD". |
Specify the password that corresponds with the specified UID. When caching data from an Oracle database, PWD specifies the TimesTen password. You can specify the Oracle PWD in the connection string, if necessary. |
None |
The value of the encrypted user password. |
None |
|
Determines whether TimesTen returns a warning if a query times out before executing. |
|
|
Assigns a connection to a replication track. |
None |
|
Specifies the time limit in seconds within which the database should execute SQL statements. |
|
|
Specifies the time limit in milliseconds within which the database should execute SQL statements. |
|
|
The threshold at which TimesTen returns a warning when the temporary partition of the database is low in memory. |
|
|
See "UID and PWD". |
Specify a user name that is defined on the TimesTen server. When caching data from an Oracle database, the UID must match the UID on the Oracle database that is being cached in TimesTen. |
None |
Specifies that the connection attempt should wait if an immediate connection is not possible. |
|
Table 2-4 NLS general connection attributes
Name | Description | Default |
---|---|---|
The character encoding for the connection, which can be different from the database character set. |
|
|
The default length semantics configuration. |
|
|
Determines whether an error is reported when there is data loss during an implicit or explicit character type conversion between |
|
|
The collating sequence to use for linguistic comparisons. |
|
Table 2-5 PL/SQL first connection attributes
Name | Description | Default |
---|---|---|
The virtual address at which the shared memory segment is loaded into each process that uses the TimesTen direct drivers. |
Platform specific |
|
The size in megabytes of the shared memory segment used by PL/SQL. |
128 MB |
|
The number of open cursors. |
|
Table 2-6 PL/SQL general connection attributes
Name | Description | Default |
---|---|---|
Controls whether the PL/SQL compiler generates cross-reference information. |
|
|
Controls conditional compilation of PL/SQL units. |
|
|
Specifies the maximum amount of process heap memory in MB that PL/SQL can use for this connection. |
|
|
The optimization level that the PL/SQL compiler uses to compile PL/SQL library units. |
|
|
The number of session cursors to cache. |
|
|
The number of seconds a PL/SQL procedure can run before being automatically terminated. |
|
Table 2-7 TimesTen Cache first connection attributes
Name | Description | Default |
---|---|---|
Enables the AWT propagation method to be used on Oracle database tables. |
|
Table 2-8 TimesTen Cache database attributes
Name | Description | Default |
---|---|---|
Indicates the number of threads necessary to apply changes to the Oracle database. |
|
|
Enables or disables the cache connection pool. |
0 |
Table 2-9 TimesTen Cache general connection attributes
Name | Description | Default |
---|---|---|
Enables or disables transparent load of data from an Oracle database to dynamic cache groups. |
1 (Enables Dynamic cache group load) |
|
Determines if an error message is returned upon a transparent load failure. |
0 (Errors are not returned) |
|
The Oracle Service Name of the Oracle database instance from which data is to be loaded into a TimesTen database. This attribute is only used by the cache agent. Set the |
None |
|
Identifies the password for the Oracle database that is being cached in TimesTen. |
None |
|
Specifies which SQL statements are executed locally in TimesTen and which SQL statements are passed through to the Oracle database for execution. |
0 |
|
Specifies whether to enable or disable the installation of Application Failover (TAF) and Fast Application Notification (FAN) callbacks. |
1 (Install callbacks) |
|
The Oracle Service Name of the standby Oracle database instance from which data is to be loaded into a TimesTen database. This attribute is only used by the cache agent in an Oracle Active Data Guard configuration. Set the |
None |
Table 2-10 TimesTen Client connection attributes
Name | Description | Default |
---|---|---|
Lists the cipher suite or suites that can be used by TLS for client server connections, depending also on the client setting |
None |
|
Identify the client server process. |
0 |
|
Specifies whether encryption is required or not for a client server connection |
|
|
Specifies whether SSL client authentication is required |
0 |
|
The port number on which the TimesTen server is listening. |
None |
|
For TimesTen Classic, the port number on which the TimesTen server should listen if an automatic failover occurs. |
None |
|
Number of seconds for the client to wait for a connect or disconnect call. |
20 seconds |
|
A range for the failover port numbers. |
None |
|
Specifies if TimesTen performs an automatic reconnect after all other failover procedures are completed. |
1 |
|
Specifies that the client randomly selects an alternate server from the list provided or selects the server according to |
0 |
|
For TimesTen Scaleout, client/server connections, defines how a client is redirected. |
1 (connect to any available server) |
|
For TimesTen Scaleout, limits the number of times the client is redirected. |
1 |
|
Indicates if the application must roll back if a client failover occurs. |
1 (enabled) |
|
Name of the computer where the TimesTen Server is running or a logical TimesTen server name. |
None |
|
If an automatic failover occurs, the name of the system where the TimesTen Server should be running or a logical TimesTen server name. |
None |
|
Server DSN corresponding to the TimesTen database. |
None |
|
For TimesTen Classic, server DSN corresponding to the TimesTen database, if an automatic failover occurs. |
None |
|
The time interval (in milliseconds) between subsequential probes. |
1000 |
|
The number of unacknowledged probes to send before considering the connection as failed and notifying the client. |
2 |
|
The duration time (in milliseconds) between the last data packet sent and the first probe. |
1000 |
|
Timeout period, in seconds, for completion of a TimesTen client/server operation. |
60 |
|
The fully qualified path to the directory where the wallet is stored. |
None |
Table 2-11 TimesTen Server connection attributes
Name | Description | Default |
---|---|---|
Lists the cipher suite or suites that can be used by TLS for client server connections, depending also on the client setting |
None |
|
Specifies whether encryption is required or not for a client server connection |
|
|
Specifies whether SSL client authentication is required |
0 |
|
The maximum number of concurrent connections a child TimesTen server process can handle. |
1 |
|
The desired number of TimesTen server processes for the DSN. |
|
|
The size in KB of the thread stack for each connection. |
|
|
The time in minutes before which the client/server session is renegotiated. |
0 |
|
The data transfer size in MB before which the client/server session is renegotiated. |
0 |
|
The fully qualified path to the directory where the wallet is stored. |
None |
Data store attributes are set at database creation time. The data store attributes are listed in Table 2-1, "Data store attributes" and described in detail in this section.
These attributes can be assigned values only during database creation by the instance administrator.
The data source name (DSN) uniquely identifies the attributes to a connection. It serves two purposes:
As a unique identifier to the ODBC driver manager (if one is present), allowing it to associate a Data Store Name with a specific ODBC driver.
As one of potentially many name aliases to a single physical database where the name alias has unique attributes associated with it.
The database attributes can apply to either the data source name (connection to a database) or the Data Store Path Name (database).
On Windows, the data source name and all configuration information associated with the data source (including the database path name) are stored in the system registry. The ODBC driver manager and TimesTen use this information.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Data Source Name
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (. dbdef ) file in TimesTen Scaleout |
DSN |
A name that describes the DSN. |
Windows ODBC Data Source Administrator | Not applicable |
The database path name uniquely identifies the physical database. It is the fully qualified directory path name of the database and the file name prefix, for example: /disk1/databases/database1
. This name is not a file name. The actual database file names have suffixes, such as .ds0
and .log0
, for example /disk1/databases/database1.ds0
and /disk1/databases/database1.log0
.
Note:
You are required to specify the database path and name at database creation time. It cannot be altered after the database has been created.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set DataStore
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
DataStore |
Full path to the physical database that the data source name references. |
Windows ODBC Data Source Administrator | Not applicable |
The database character set determines the character set in which data is stored.
Note:
You are required to specify the database character set at database creation time only. It cannot be altered after the database has been created. If you do not specify a value for this attribute when creating a database, TimesTen returns error message 12701.Generally, your database character set should be chosen based on the data requirements. For example: Do you have data in Unicode or is your data in Japanese on UNIX and Linux systems (EUC
) or Windows (SJIS
)?
You should choose a connection character set that matches your terminal settings or data source. See "ConnectionCharacterSet".
When the database and connection character sets differ, TimesTen performs the data conversion internally based on the connection character set. If the connection and database character sets are the same, TimesTen does not need to convert or interpret the data set. Best performance occurs when connection and database character sets match, since no conversion is required.
To use this attribute you must specify a supported character set. For a list of supported character set names, see "Supported character sets" below.
There are several things to consider when choosing a character set for your database. For a discussion about these considerations, see "Choosing a database character set" in Oracle TimesTen In-Memory Database Operations Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set DatabaseCharacterSet
name as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
DatabaseCharacterSet |
Specify the preferred character set. |
Windows ODBC Data Source Administrator | Not applicable |
The tables in this section describe the character sets supported in TimesTen.
Name | Description |
---|---|
JA16EUC |
EUC 24-bit Japanese |
JA16EUCTILDE |
The same as JA16EUC except for the way that the wave dash and the tilde are mapped to and from Unicode |
JA16SJIS |
Shift-JIS 16-bit Japanese |
JA16SJISTILDE |
The same as JA16SJIS except for the way that the wave dash and the tilde are mapped to and from Unicode |
KO16KSC5601 |
KSC5601 16-bit Korean |
KO16MSWIN949 |
Microsoft Windows Code Page 949 Korean |
TH8TISASCII |
Thai Industrial Standard 620-2533 - ASCII 8-bit |
VN8MSWIN1258 |
Microsoft Windows Code Page 1258 8-bit Vietnamese |
ZHS16CGB231280 |
CGB2312-80 16-bit Simplified Chinese |
ZHS16GBK |
GBK 16-bit Simplified Chinese |
ZHS32GB18030 |
GB18030-2000 |
ZHT16BIG5 |
BIG5 16-bit Traditional Chinese |
ZHT16HKSCS |
Microsoft Windows Code Page 950 with Hong Kong Supplementary Character Set HKSCS-2001 . Character set conversion to and from Unicode is based on Unicode 3.0. |
ZHT16MSWIN950 |
Microsoft Windows Code Page 950 Traditional Chinese |
Name | Description |
---|---|
BLT8CP921 |
Latvian Standard LVS8-92( 1) Windows/UNIX/Linux 8-bit Baltic |
BLT8ISO8859P13 |
ISO 8859-13 Baltic |
BLT8MSWIN1257 |
Microsoft Windows Code Page 1257 8-bit Baltic |
BLT8PC775 |
IBM-PC Code Page 775 8-bit Baltic |
CEL8ISO8859P14 |
ISO 8859-13 Celtic |
CL8ISO8859P5 |
ISO 8859-5 Latin/Cyrillic |
CL8KOI8R |
RELCOM Internet Standard 8-bit Latin/Cyrillic |
CL8KOI8U |
KOI8 Ukrainian Cyrillic |
CL8MSWIN1251 |
Microsoft Windows Code Page 1251 8-bit Latin/Cyrillic |
EE8ISO8859P2 |
ISO 8859-2 East European |
EL8ISO8859P7 |
ISO 8859-7 Latin/Greek |
ET8MSWIN923 |
Microsoft Windows Code Page 923 8-bit Estonian |
EE8MSWIN1250 |
Microsoft Windows Code Page 1250 8-bit East European |
EL8MSWIN1253 |
Microsoft Windows Code Page 1253 8-bit Latin/Greek |
EL8PC737 |
IBM-PC Code Page 737 8-bit Greek/Latin |
EE8PC852 |
IBM-PC Code Page 852 8-bit East European |
LT8MSWIN921 |
Microsoft Windows Code Page 921 8-bit Lithuanian |
NE8ISO8859P10 |
ISO 8859-10 North European |
NEE8ISO8859P4 |
ISO 8859-4 North and North-East European |
RU8PC866 |
IBM-PC Code Page 866 8-bit Latin/Cyrillic |
SE8ISO8859P3 |
ISO 8859-3 South European |
US7ASCII |
ASCII 7-bit American |
US8PC437 |
IBM-PC Code Page 437 8-bit American |
WE8ISO8859P1 |
ISO 8859-1 West European |
WE8ISO8859P15 |
ISO 8859-15 West European |
WE8MSWIN1252 |
Microsoft Windows Code Page 1252 8-bit West European |
WE8PC850 |
IBM-PC Code Page 850 8-bit West European |
WE8PC858 |
IBM-PC Code Page 858 8-bit West European |
Name | Description |
---|---|
AR8ADOS720 |
Arabic MS-DOS 720 Server 8-bit Latin/Arabic |
AR8ASMO8X |
ASMO Extended 708 8-bit Latin/Arabic |
AR8ISO8859P6 |
ISO 8859-6 Latin/Arabic |
AR8MSWIN1256 |
Microsoft Windows Code Page 1256 8-Bit Latin/Arabic |
AZ8ISO8859P9E |
ISO 8859-9 Latin Azerbaijani |
IW8ISO8859P8 |
ISO 8859-8 Latin/Hebrew |
IW8MSWIN1255 |
Microsoft Windows Code Page 1255 8-bit Latin/Hebrew |
TR8MSWIN1254 |
Microsoft Windows Code Page 1254 8-bit Turkish |
TR8PC857 |
IBM-PC Code Page 857 8-bit Turkish |
WE8ISO8859P9 |
ISO 8859-9 West European & Turkish |
Optionally, set this attribute to help you identify the Data Source Name (DSN
) and its attributes.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Description
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Description |
Text description of the Data Source Name. This attribute is optional. |
Windows ODBC Data Source Administrator | Not applicable |
The Driver
attribute specifies the name of the TimesTen ODBC Driver.
For example, on Windows systems the value can be TimesTen Client 18.1
.
On UNIX and Linux systems, the value of the Driver
attribute is the path name of the TimesTen ODBC Driver shared library file, timesten_home
/install/lib/libtten.so
.
For more information, see "Creating a DSN on Linux and UNIX for TimesTen Classic" in Oracle TimesTen In-Memory Database Operations Guide.
For general usage scenarios, refer to standard ODBC reference documentation, such as
https://docs.microsoft.com/en-us/sql/odbc/reference/syntax/odbc-api-reference
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Driver
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Driver |
Specifies the path name for the TimesTen ODBC Driver shared library file, if using a Driver Manager. |
Windows ODBC Data Source Administrator | Select a driver from the Create New Data Source dialog. | Specifies the Client driver for TimesTen and the release. |
For TimesTen Scaleout, the setting of this attribute determines the durability of "prepare-to-commit" and commit records.
If K-safety is set to 2, the default value is 0
.
If K-safety is set to 1, the default value is 1
.
Durability=0
is not supported with K-safety set to 1.
For details about setting up K-safety, see "Creating a grid" in the Oracle TimesTen In-Memory Database Scaleout User's Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is not supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Durability
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems database definition (.dbdef ) file in TimesTen Scaleout |
Durability |
0 - TimesTen does not write the transaction prepare-to-commit and commit records to disk on transaction commit.
|
Windows ODBC Data Source Administrator | N/A |
The LogDir
attribute specifies the fully qualified directory path name where database logs reside. Specifying this attribute enables you to place the transaction log files on a different I/O path from the database checkpoint files. Placing the transaction log files and checkpoint files on different disks can improve system performance.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogDir
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogDir |
Specifies the directory where transaction log files reside. |
Windows ODBC Data Source Administrator | Not applicable |
The Preallocate
attribute determines whether TimesTen preallocates disk space for the database checkpoint files when the database is created. Setting this attribute ensures that there is sufficient space for the database when the database is saved to the file system.
TimesTen respects the setting for the Preallocate
attribute for all operations that create a new checkpoint file, such as database creation, ttRepAdmin -duplicate
, and ttRestore
.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Preallocate
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Preallocate |
0 - Does not preallocate disk space for checkpoint files when creating the database.
|
Windows ODBC Data Source Administrator | Not applicable |
Note:
reallocating disk space for a large database is very time consuming.Enables parallel replication when used with the ReplicationParallelism
attribute. With parallel replication, multiple transmitters on the master send to multiple receivers on the subscriber.
Automatic parallel replication: Parallel replication over multiple threads that automatically enforces transactional dependencies and all changes applied in commit order. This is the default.
Automatic parallel replication with disabled commit dependencies: Parallel replication over multiple threads that automatically enforces transactional dependencies, but does not enforce transactions committed in the same order on the subscriber database as on the active database. You can also increase replication throughput by applying transactions to specific tracks.
For more details on configuring parallel replication, see "Configuring parallel replication" in the Oracle TimesTen In-Memory Database Replication Guide.
This attribute also sets parallel propagation for AWT cache groups. By default, this attribute enables parallel propagation of updates to the Oracle database. To learn more about parallel AWT caching, see "Configuring parallel propagation to Oracle Database tables" in the Oracle TimesTen Application-Tier Database Cache User's Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set ReplicationApplyOrdering
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ReplicationApplyOrdering |
0 - Specifies automatic parallel replication. Automatic parallel replication is available for both classic and active standby pair replication schemes. (default)
|
Windows ODBC Data Source Administrator | Not applicable |
Restrictions when using automatic parallel replication with disabled commit dependencies:
The replication scheme must be an active standby pair that uses asynchronous replication. Classic replication schemes are not supported.
The replication scheme cannot contain cache groups.
This is only supported for TimesTen Release 11.2.2.8 and greater for both the active and standby masters. Both the active and standby masters must have commit dependencies disabled.
XLA is not supported.
All data stores in the replication scheme must use the same setting.
This attribute specifies the number of tracks, or the number of transmitter/receiver pairs, used for automatic parallel replication.
Set ReplicationParallelism to a number from 2 to 32. The number cannot exceed half the value of LogBufParallelism. This number indicates the number of transmitter threads on the source database and the number of receiver threads on the target database. However, if you are using single-threaded replication, set ReplicationParallelism to 1, the default.
To learn more about automatic parallel replication, see "Configuring parallel replication" in the Oracle TimesTen In-Memory Database Replication Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set ReplicationParallelism
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ReplicationParallelism |
n - A value between 1 and 32, indicating the number of tracks to replicate in parallel. The default is 1. |
Windows ODBC Data Source Administrator | Not applicable |
Restrictions and things to consider when specifying parallel replication include:
When parallel replication is enabled, the Description column of the ttLogHolds
built-in procedure displays one row per track per subscriber node.
We recommend setting the value of this attribute to a value no greater than half the value of the LogBufParallelism
attribute. If you specify more replication tracks than log buffer threads, some replication tracks can remain empty.
Set this attribute to create a temporary database. Temporary databases are not saved to the file system. They may, however, be shared and therefore require a data store path name. A temporary database is deleted when the last connection is closed. You cannot assign the Temporary data store attribute to an existing permanent database.
Note:
You cannot back up or replicate a temporary database.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set Temporary
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
Temporary |
0 (default) - Creates a permanent database.
|
Windows ODBC Data Source Administrator | Not applicable |
TimesTen sets first connection attributes when a database created by the instance administrator is loaded into memory and persist for the first connection and all subsequent connections until the last connection to this database is closed.
You can modify first connection attributes only when the TimesTen database is unloaded. Then the instance administrator reconnects with new values for the first connection attributes.
First connection attributes are listed in Table 2-2, "First connection attributes" and described in detail in this section.
If you try to connect to the database using attributes that are different from the first connection attribute settings, the new connection can be rejected or the attribute value can be ignored. However, for example, if existing connections have a LogFileSize
of one size and a new connection specifies a LogFileSize
of another size, TimesTen ignores the new value and returns a warning.
Note:
Only the instance administrator can change a first connection attribute to a value other than the one currently in effect. To change the value of a first connection attribute, you must first shut down the database and then connect withADMIN
privileges. (No privileges are required to change AutoCreate
and ForceConnect
.)If you connect to a database that has the AutoCreate
attribute set and the database does not exist yet, the database is created automatically if you supplied a valid existing path. With AutoCreate
set, TimesTen creates the database, but not the path to the database. If you attempt to connect to a database that does not exist and the AutoCreate
attribute is not set, the connection fails.
Also see "Overwrite".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set AutoCreate
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
AutoCreate |
0 - Does not create new database if database does not exist.
|
Windows ODBC Data Source Administrator | Not applicable |
Controls the number of transaction log files that accumulate in the directory defined by the value of the LogDir
attribute after a backup starts before TimesTen releases the hold on checkpoint operations. If a checkpoint is initiated before the completion of a backup, the backup is invalidated.
TimesTen temporarily ignores the CkptFrequency and CkptLogVolume attributes (controlling background checkpoints) while a backup is in progress if this attribute is not set or is set to 0
.
Set the attribute to a value that is high enough to ensure the safe completion of your backup. For example, if a backup typically takes n seconds to complete and your database creates m transaction log files per second, set BackupFailthreshold
to a value greater than n*
m.
The number of log files generated by your database per any given unit of time is directly proportional to your write workload and inversely proportional to the value set for the LogFileSize attribute.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set BackupFailThreshold
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
BackupFailThreshold |
Enter a non-zero integer value that indicates the number of transaction log files that are allowed to accumulate before the backup fails.
The default is |
Windows ODBC Data Source Administrator | Not applicable |
Controls the frequency in seconds that TimesTen performs a background checkpoint. The counter used for the checkpoint condition is reset at the beginning of each checkpoint.
If both CkptFrequency
and CkptLogVolume
attributes have a value greater than 0, a checkpoint is performed when either of the two conditions becomes true. The values set by the ttCkptConfig
built-in procedure replace the values set by these attributes.
In the case that your application attempts to perform a checkpoint operation while a background checkpoint is in process, TimesTen waits until the background checkpoint finishes and then executes the application's checkpoint.
When using TimesTen Scaleout, if Durability = 0,
set EpochInterval
to a value less than the value of the CkptFrequency
when Durability=0
to guarantee at least 1 epoch per interval.
The value of this attribute is "sticky" as it persists across database loads and unloads unless it is explicitly changed. The default value is only used during database creation. Subsequent first connections default to using the existing value stored in the database.
When the value of this attribute is more than 0
, if a checkpoint fails, TimesTen attempts a checkpoint once every 30 seconds. If a checkpoint failure occurs due to a lack of file system space, we recommend that you attempt a manual checkpoint as soon as space is available. Once any successful checkpoint occurs, background checkpointing reverts to the configured schedule.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CkptFrequency
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
CkptFrequency |
Enter a value in seconds for the frequency at which TimesTen should perform a background checkpoint. The default is 0 .
If you do not specify this attribute with a value, TimesTen does not perform background checkpoints. For an existing database, TimesTen uses the stored value. |
Windows ODBC Data Source Administrator | Not applicable |
Controls the amount of data in megabytes that collects in the log between background checkpoints. The counter used for the checkpoint condition is reset at the beginning of each checkpoint.
If both CkptFrequency
and CkptLogVolume
attributes have a value greater than 0, a checkpoint is performed when either of the two conditions becomes true. The values set by the ttCkptConfig
built-in procedure replace the values set by these attributes.
In the case that your application attempts to perform a checkpoint operation while a background checkpoint is in process, TimesTen waits until the background checkpoint finishes and then executes the application's checkpoint.
The value of this attribute is "sticky" as it persists across database loads and unloads unless it is explicitly changed. The default value is only used during database creation. Subsequent first connections default to using the existing value stored in the database.
When the value of this attribute is more than 0
and CkptFrequency=0
, if a checkpoint fails, TimesTen attempts a checkpoint every 30 seconds. If a checkpoint failure occurs due to a lack of file system space, we recommend that you attempt a manual checkpoint as soon as space is available. Once any successful checkpoint occurs, background checkpointing reverts to the configured schedule.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CkptLogVolume
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
CkptLogVolume |
Specify the amount of data in megabytes that can accumulate in the transaction log file between background checkpoints. The default is the value supplied for the LogFileSize attribute.
For an existing database, TimesTen uses the stored value. If the attribute is specified, but you do not supply a value, TimesTen uses the value supplied for the LogFileSize attribute. |
Windows ODBC Data Source Administrator | Not applicable |
Controls the maximum rate at which data should be written to disk during a checkpoint operation. This can be useful when the writing of checkpoints to disk interferes with other applications.
All background checkpoints and by checkpoints initiated by the ttCkpt
and ttCkptBlocking
built-in procedures use the rate specified by this connection attribute. Foreground checkpoints (checkpoints taken during first connect and last disconnect) do not use this rate. The rate is specified in MB per second.
A value of 0
disables rate limitation. This is the default. The value can also be specified using the ttCkptConfig
built-in procedure. The value set by the ttCkptConfig
built-in procedure replaces the value set by this attribute.
The value of this attribute is "sticky" as it persists across database loads and unloads unless it is explicitly changed. The default value is only used during database creation. Subsequent first connections default to using the existing value stored in the database. If left unspecified (or empty in the Windows ODBC Data Source Administrator), TimesTen uses the stored setting. To turn the attribute off, you must explicitly specify a value of 0
. For existing databases that are migrated to this release, the value is initialized to 0
. To use the current or default value, the attribute value should be left unspecified.
For more details about the benefits of and issues when using CkptRate
, see "Setting the checkpoint rate" in Oracle TimesTen In-Memory Database Operations Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CkptRate
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
CkptRate |
Specify the maximum rate in MB per second at which a checkpoint should be written to disk.
A value of If you do not specify this attribute, TimesTen uses the default value ( If the attribute is specified, but you do not supply a value, the value of Specifying a value of |
Windows ODBC Data Source Administrator | Not applicable |
Determines the number of threads used to read the checkpoint file when loading the database into memory, such as in first connection or recovery operations.
When the CkptReadThreads
attribute is set to 1
, TimesTen reads checkpoint files serially. When the CkptReadThreads
attribute is set to a value greater than 1
, TimesTen uses the specified number of threads to read checkpoint files concurrently (in parallel). When the CkptReadThreads
attribute is set to 0
or unspecified, the previously specified value is used.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CkptReadThreads
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
CkptReadThreads |
n - The number of threads to use when reading the checkpoint files during the loading of the database into memory. Takes an integer value of 0 or greater (maximum = 2 31-1 ). Default is 1 . |
Windows ODBC Data Source Administrator | Not applicable |
Indicates the upper bound on the number of user-specified concurrent connections to the database. TimesTen allocates one semaphore for each expected connection. If the number of connections exceeds the value of this attribute, TimesTen returns an error.
The number of current connections to a database can be determined by viewing the output from the ttStatus
utility.
As a guideline, set this value to the maximum number of expected application connections plus ten percent.
If you receive an error indicating that the number of connections exceeds the value of this attribute, increase the value until you no longer receive this error.
There is both a fixed and per connection overhead allocated from the PL/SQL segment, even if you do not use PL/SQL. For details, see "PLSQL_MEMORY_SIZE".
Note:
The kernel must be configured with enough semaphores to handle all active databases. For details on setting semaphores for your system, see "Operating system prerequisites" in Oracle TimesTen In-Memory Database Installation, Migration, and Upgrade Guide or "Operating system prerequisites" in Oracle TimesTen In-Memory Database Scaleout User's Guide.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Connections
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Connections |
The default value is the lesser of 2000 or the number of semaphores specified in the SEMMNS kernel parameter minus 155 .
A legal value is an integer from |
Windows ODBC Data Source Administrator | Not applicable |
For TimesTen TimesTen Scaleout, use this attribute to set the number of seconds between epochs.
If Durability = 1, the default for this attribute is 0. (System does not generate periodic epochs)
If Durability = 0, the default for this attribute is 1. You must set this attribute to a value less than the value of the CkptFrequency
when Durability=0
to guarantee at least 1 epoch per interval.
If this attribute is set to 0
, the system does not generate periodic epochs. An application can generate epochs at custom intervals by calling the ttEpochCreate
built-in procedure each time the application wants to create an epoch.If an element is down, an epoch interval can be skipped.
As long as one element in each replica set is up, the system never skips more than K*EpochInterval
seconds between epochs.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is not supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set EpochInterval
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems database definition (.dbdef ) file in TimesTen Scaleout |
EpochInterval |
0 - TimesTen does not generate periodic epochs.
|
Windows ODBC Data Source Administrator | N/A |
When return receipt replication is used with the NONDURABLE TRANSMIT
option, a failed master database is allowed to recover only by restoring its state from a subscriber database using the -duplicate
option of the ttRepAdmin
utility. In other words, the failed database cannot just come up and have replication bring it up to date because it may lose some transactions that were transmitted to the subscriber but not durably committed locally. The ForceConnect
connection attribute overrides this restriction.
The ttConfiguration
built-in procedure does not return the value of the ForceConnect
attribute.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set ForceConnect
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ForceConnect |
0 (default) - Do not allow connection to failed database if it is not properly restored from the corresponding subscriber database.
|
Windows ODBC Data Source Administrator | Not applicable |
Allows you to force disconnection from the database using ttAdmin -disconnect
. See "Force disconnect".
The ttConfiguration
built-in procedure does not return the value of the ForceDisconnectEnabled
attribute.
Notes:
By default, the forced disconnect feature is disabled. Existing direct-connect applications may find it undesirable for TimesTen to spawn the thread that is required to implement this functionality.
Users should not specify different values of this attribute for different database connections. If the force disconnect feature is desired, add ForceDisconnectEnabled=1
to the DSN definition in the sys.odbc.ini
file.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set ForceDisconnectEnabled
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ForceDisconnectEnabled |
0 (default) - Do not allow forced disconnections.
|
Windows ODBC Data Source Administrator | N/A |
Determines whether the first connection to the database should proceed if TimesTen recovery encounters a defective log record.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogAutoTruncate
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogAutoTruncate |
0 - If a defective log record is encountered, terminate recovery and return an error to the connecting application. Checkpoint and transaction log files remain unmodified.
|
Windows ODBC Data Source Administrator | Not applicable |
For TimesTen Classic,The LogBufMB
attribute specifies the size of the internal transaction log buffer in megabytes, for the database.
For TimesTen Scaleout,The LogBufMB
attribute specifies the size of the internal transaction log buffer in megabytes, for the element.
The recommendation is to set LogBufMB
to a value between 256 MB and 4 GB. If memory space is a concern, start with 256 MB; otherwise, start with 1 GB.
If you change the value of LogBufMB
, you also may need to change the value of LogBufParallelism
to satisfy the constraint that LogBufMB
/LogBufParallelism
>= 8
.
If you increase the value of LogBufMB
, ensure the value of LogFileSize
is greater than or equal to the value of LogBufMB
(LogFileSize >= LogBufMB
).
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogBufMB
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogBufMB |
n - Size of log buffer in megabytes.
If not set and the database or element exists, TimesTen uses the value stored in the database. If not set and the database or element is being created, TimesTen uses the default value of The maximum value is 65,536 MB (64 GB). |
Windows ODBC Data Source Administrator | Not applicable |
The LogBufParallelism
attribute specifies the number of transaction log buffer strands to which TimesTen writes log files before the log is written to disk, allowing for improved log performance. Strands divide the transaction log buffer available memory into a number of different regions, which can be accessed concurrently by different connections. Each connection can execute data-independent DML statements in parallel using those strands as if each has its own transaction log buffer.
Each buffer has its own insertion latch. Records are inserted in any of the strands. The log flusher gathers records from all strands and writes them to the log files.
If you change the value of LogBufParallelism
, you also may need to change the value of LogBufMB
to satisfy the constraint that LogBufMB
/LogBufParallelism
>= 8.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogBufParallelism
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogBufParallelism |
An integer value between 1 and 64. Default is 4 . |
Windows ODBC Data Source Administrator | Not applicable |
The LogFileSize
attribute specifies the maximum size of transaction log files in megabytes. The minimum value is 8 MB. The default value is 64 MB. If you specify a size smaller than 8 MB, TimesTen returns an error message. Before TimesTen release 11.2.1.4, the minimum size was 1 MB. If you created your database in a previous release of TimesTen and specified a log file size of less than 8 MB, you must increase the value assigned to this attribute to avoid an error.
Actual transaction log file sizes can be slightly smaller or larger than LogFileSize
because log records cannot span transaction log files.
If you specify a value of zero, TimesTen uses the default transaction log file size if the database does not exist. If the database exists, TimesTen uses the current specified transaction log file size.
Set the value of LogFileSize
to be larger than or equal to the value of LogBufMB
(LogFileSize >= LogBufMB
).
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogFileSize
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogFileSize |
n - Size of transaction log file in megabytes. Default is the value of LogBufMB when the database is created and 0 (current size in effect) on subsequent connections. The minimum size is 8 MB.
The maximum value is 65,536 MB (64 GB). |
Windows ODBC Data Source Administrator | Not applicable |
Controls the method used by TimesTen to write and sync log data to transaction log files. The overall throughput of a system can be significantly affected by the value of this attribute, especially if the application chooses to commit most transactions durably.
As a general rule, use the value 1 if most of your transactions commit durably and use the value 0 otherwise.
For best results, however, experiment with both values using a typical workload for your application and platform. Although application performance can be affected by this attribute, transaction durability is not affected. Changing the value of this attribute does not affect transaction durability in any way.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogFlushMethod
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogFlushMethod |
0 (default) - Write data to transaction log files using buffered writes and use explicit sync operations as needed to sync log data to disk (for example with durable commits).
|
Windows ODBC Data Source Administrator | Not applicable |
If the LogPurge
attribute is set, TimesTen automatically removes transaction log files when they have been written to both checkpoint files and there are no transactions that still need the transaction log files' contents. The first time checkpoint is called, TimesTen writes the contents of the transaction log files to one of the checkpoint files. When checkpoint is called the second time, TimesTen writes the contents of the transaction log files to the other checkpoint file.
TimesTen purges the transaction log files if all these conditions are met:
The contents of the transaction log files have been written to both checkpoint files.
The transaction log files are not pending incremental backup.
If replication is being used, the transaction log files have been replicated to all subscribers.
If XLA is being used, all XLA bookmarks have advanced beyond the transaction log files.
The transaction log files are not being used by any distributed transactions using the XA interface.
If this attribute is set to 0
or unchecked, unneeded transaction log files are appended with the.arch
suffix. Applications can then delete the files.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LogPurge
as follows:
Where to set the attributes | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LogPurge |
0 - Does not remove old transaction log files at connect and checkpoint.
|
Windows ODBC Data Source Administrator | Not applicable |
On Windows systems, TimesTen enables applications that connect to a shared database to specify whether the real memory should be locked while the database is being loaded into memory or while the store is in memory. If the physical memory used for the database is locked, the operating system's virtual memory subsystem cannot borrow that memory for other uses. No part of the database is ever paged out but this could lead to memory shortages in a system that is under configured with RAM. While memory locking can improve database load performance, it may impede other applications on the same computer.
On Linux, MemoryLock=4
will try to obtain a MemoryLock
based on what the operating system allows. On Linux, locking all of the virtual memory size (physical + swap) can occur. TimesTen performs best if it does not use swap. Since the operating system allows locking more memory than is actually available, it is important to carefully configure the operating system memory management parameters to limit the amount of lockable memory. You can configure these parameters in the /etc/security/limits.conf
file.
On AIX the MemoryLock
attribute is not implemented.
The PL/SQL shared memory segment is not subject to MemoryLock
.
On Linux systems, set the groupname
in the MemLock
setting to be the same as the instance administrator in the /etc/security/limits.conf
file. Set the value of MemLock
to be at least as large as the TimesTen database shared memory segment.
To view privileges, use:
% ppriv $$
To add the privilege for user ID timesten
, a root user uses:
# usermod -K defaultpriv=basic,proc_lock_memory timesten
After adding the privilege, the timesten
user must log in to a new shell, unload all TimesTen databases from memory and restart the TimesTen daemons.
To restart the TimesTen daemons, in the new login shell, use:
% ttDaemonadmin -restart
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set MemoryLock
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
MemoryLock |
0 (default) - Does not lock memory.
|
Windows ODBC Data Source Administrator | Not applicable |
If the Overwrite
attribute is set and there is an existing database with the same database path name as the new database, TimesTen destroys the existing database and creates a new empty database if the existing database is not in use. If the Overwrite
attribute is set and there is not a database with the specified database path name, TimesTen only creates a new database if the AutoCreate
attribute is also set (see "AutoCreate"). TimesTen ignores the Overwrite
attribute if AutoCreate
is set to 0. Applications should use caution when specifying the Overwrite
=1 attribute.
Only the instance administrator can change the value of this attribute. If a user other than an instance administrator attempts to connect to a database with Overwrite
=1, TimesTen returns an error.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set Overwrite
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
Overwrite |
0 (default) - TimesTen does not overwrite an existing database with the same path name.
|
Windows ODBC Data Source Administrator | N/A |
For TimesTen Classic, indicates the size in MB of the permanent memory region for the database.
For TimesTen Scaleout, indicates the size in MB of the permanent memory region for the element.
You may increase PermSize
at first connect but not decrease it. TimesTen returns a warning if you attempt to decrease the permanent memory region size. If the database does not exist, a PermSize
value of 0
or no value indicates to use the default size. Default size is 32 MB. For an existing database, a value of 0 or no value indicates that the existing size should not be changed.
Once you have created a database, you can make the permanent partition larger, but not smaller. See "Specifying the memory region sizes of a database" in Oracle TimesTen In-Memory Database Operations Guide.
Also see information about the TempSize
connection attribute.
The ttMigrate
and ttDestroy
utilities can also be used to change the Permanent Data Size, when appropriate.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PermSize
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PermSize |
n - Size of permanent partition in megabytes; default is 32 MB. Minimum size is 32 MB. |
Windows ODBC Data Source Administrator | Not applicable |
The RecoveryThreads
attribute determines the number of threads used to rebuild indexes during recovery.
If RecoveryThreads
=1, during recovery, indexes that must be rebuilt are done serially. If you have enough processors available to work on index rebuilds on your computer, setting this attribute to a number greater than 1 can improve recovery performance. The performance improvement occurs only if different processors can work on different indexes. There is no parallelism in index rebuild within the same index.
The value of RecoveryThreads
can be any value up to the number of CPUs available on your system.
The default is 1 when the database is created. Upon subsequent connections, if the database must be recovered and RecoveryThreads is unspecified or has a value of 0, then TimesTen uses the previous setting for this attribute.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set RecoveryThreads
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
RecoveryThreads |
n - The number of threads to use when rebuilding indexes during recovery. Default is 4 when the database is created and 0 on subsequent connections. |
Windows ODBC Data Source Administrator | Not applicable |
For TimesTen Classic, TempSize
indicates the total amount of memory in MB allocated to the temporary region for the database
For TimesTen Scaleout, indicates the total amount of memory in MB allocated to the temporary region for an element
TempSize
has no predefined value. If left unspecified, its value is determined from PermSize
as follows:
If PermSize
is less than 64 MB, TempSize = 32 MB + ceiling(PermSize / 4 MB
).
Otherwise, TempSize = 40 MB + ceiling(PermSize / 8 MB)
.
TimesTen rounds the value up to the nearest MB.
If specified, TimesTen always honors the TempSize
value. Since the temporary data partition is recreated each time a database is loaded, the TempSize
attribute can be increased or decreased each time a database is loaded. For an existing database, a value of 0 or no value indicates that the existing size should not be changed. The minimum TempSize
is 32 MB.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TempSize
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TempSize |
n - Size of the temporary partition, in MB. Minimum size is 32 MB on all platforms. |
Windows ODBC Data Source Administrator | Not applicable |
General connection attributes are set by each connection and persist for the duration of the connection. General connection attributes are listed in Table 2-3, "General connection attributes" and described in detail in this section.
Use this attribute to determine the time limit in milliseconds to wait for a response to a channel create request. The value used for the channel create timeout is determined by comparing the values set for the ChannelCreateTimeout
, SQLQueryTimeoutMSec
and SQLQueryTimeout
connection attributes.
If ChannelCreateTimeout
, SQLQueryTimeout
and SQLQueryTimeoutMSec
are non-zero, then the timeout used is the minimum value of these connection attributes.
If ChannelCreateTimeout
is set to 0
, then irrespective of the value of SQLQueryTimeout
, channel timeout feature will be disabled and channel creation will be synchronous.
If ChannelCreateTimeout
is set to a non-zero value and SQLQueryTimeout
or SQLQueryTimeoutMSec
are all set to 0
, then the value of ChannelCreateTimeout
is the timeout for channel creation.
Note:
If the timeout used is different than what is configured in theChannelCreateTimeout
connection attribute, TimesTen does not overwrite the value set for the ChannelCreateTimeout
connection attribute.See "Choose SQL and PL/SQL timeout values" in the Oracle TimesTen In-Memory Database Operations Guide for more information.
The timeout for channel create should not exceed the value specified for TTC_Timeout
, which is a timeout for when the TimesTen Client application waits for a result from the corresponding TimesTen Server process. See "TTC_Timeout" for details on this connection attribute.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is not supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set ChannelCreateTimeout
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems database definition (.dbdef ) file in TimesTen Scaleout |
ChannelCreateTimeout |
n - Time limit in milliseconds for how long to wait on a create channel request. The value of n can be any integer equal to or greater than 0. The default value is 30,000 milliseconds (30 seconds). If you set the value to 0 , then the query does not time out. |
Windows ODBC Data Source Administrator | Not applicable |
CommitBufferSizeMax
indicates the total amount of memory in MB allocated to the transaction commit buffer. Set this attribute to handle the size of reclaim records.
You can use the ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference, to assign or change the maximum size of the commit buffer within a session. The new value takes effect when a new transaction starts.
ALTER SESSION SET COMMIT_BUFFER_SIZE_MAX = n;
You can see the configured maximum for the commit buffer by calling the ttConfiguration
built-in procedure.
For more information on reclaim operations, including details about setting the commit buffer size, see "Transaction reclaim operations" in the Oracle TimesTen In-Memory Database Operations Guide. Also see information about the ttCommitBufferStats
and the ttCommitBufferStatsReset
built-in procedures.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CommitBufferSizeMax
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
CommitBufferSizeMax |
0 - Commit buffer is configured to the default size. (10MB).
|
Windows ODBC Data Source Administrator | Not applicable |
When you call the built-in procedure ttCommitBufferStats
, the commit buffer statistics are expressed in bytes. However, the ttConfiguration
built-in procedure output and the value set by the connection attribute CommitBufferSizeMax
are expressed in MB.
This attribute is also available as a Client connection attribute.
This attribute enables you to attach a symbolic name to any database connection. Connection names are unique within a process.
TimesTen uses the symbolic name to help identify the connection in various administrative utilities, such as ttIsql
, ttXactAdmin
and ttStatus
. This can be particularly useful with processes that make multiple connections to the database, as is typical with multithreaded applications or in the identification of remote clients.
The value of this attribute is intended to be dynamically defined at connection time using the connection string. The default value is the connecting executable file name. It can also be defined statically in the DSN definition. Values used for ConnectionName
should follow SQL identifier syntax rules.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set ConnectionName
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
ConnectionName |
Enter a string up to 30 characters that represents the name of the connection. If the specified or default connection name is in use, TimesTen assigns the name con n , where n is an integer greater than 0 to make the name unique. If not specified, the connecting process name. |
Windows ODBC Data Source Administrator | Connection field on the Oracle TimesTen Client DSN Setup dialog | Enter a string up to 30 characters that represents the name of the connection. If the specified or default connection name is in use, TimesTen assigns the name con n , where n is an integer greater than 0 to make the name unique. If not specified, the connecting process name. |
For TimesTen Scaleout, specifies if each commit generates an epoch.
Set this general connection attribute to '1' to make every commit from this connection an epoch. Default value is '0' which will make it so commits are not epochs unless the transaction included a call to the ttEpochCreate
built-in procedure.'
TimesTen Classic ignores this attribute.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is not supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set CreateEpochatCommit
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems database definition (.dbdef ) file in TimesTen Scaleout |
CreateEpochatCommit |
0 (default) - TimesTen does not write the transaction log to disk on transaction commit.
|
Windows ODBC Data Source Administrator | Not applicable |
Determines whether a table or a sequence is included in an active standby pair replication scheme when created. The table can be included if the DDLReplicationLevel
connection attribute is set to 2 or 3. The sequence can be included if the DDLReplicationLevel
connection attribute is set to 3.
Replication of DDL operations is enabled (with restrictions) by the set value of the DDLReplicationLevel
connection attribute. For more details, see "DDLReplicationLevel".
The value can be modified by an ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET DDL_REPLICATION_ACTION='EXCLUDE';
Values set by ALTER SESSION
override the value set by this attribute.
For examples of altering an active standby pair, see "Altering an Active Standby Pair" in the Oracle TimesTen In-Memory Database Replication Guide.
DDL operations are automatically committed. When RETURN TWOSAFE
has been specified, errors and timeouts may occur as described in "RETURN TWOSAFE" in the Oracle TimesTen In-Memory Database Replication Guide. If a RETURN TWOSAFE
timeout occurs, the DDL transaction is committed locally regardless of the LOCAL COMMIT ACTION
that has been specified.
To learn more about replicating DDL, see "Making DDL changes in an active standby pair" in the Oracle TimesTen In-Memory Database Replication Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set DDLReplicationAction
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
DDLReplicationAction |
INCLUDE (default) - When a table or sequence is created, it is automatically added to the active standby pair scheme when the appropriate DDLReplicationLevel value is configured.
|
Windows ODBC Data Source Administrator | Not applicable |
Enables replication of a subset of data definition language (DDL) statements (with restrictions) in an active standby replication scheme.
When the value of the DDLReplicationLevel
connection attribute is set to 1, CREATE
or DROP
statements for tables, indexes, or synonyms are not replicated to the standby database. However, you can add or drop columns with the ALTER TABLE ADD
or DROP COLUMN
to or from a replicated table, and those actions are replicated to the standby database.
When the value of the DDLReplicationLevel
connection attribute is set to 2 (the default), the following DDL statements (described in Oracle TimesTen In-Memory Database SQL Reference) are replicated to the standby and any subscribers:
CREATE TABLE
or DROP TABLE
(including global temporary tables but not CREATE TABLE AS SELECT
)
When the value of the DDLReplicationLevel
connection attribute is set to 3, the following DDL statements (described in Oracle TimesTen In-Memory Database SQL Reference) and those replicated when the value is set to 2 are replicated to the standby and any subscribers:
Replication of the results to the standby master when setting the cache administration user name and password with the UidPwdSet
built-in procedure. You do not need to stop and restart the cache agent or replication agent to execute the UidPwdSet
built-in procedure. For more information, see "Changing cache user names and passwords" in the Oracle TimesTen Application-Tier Database Cache User's Guide or "ttCacheUidPwdSet".
The value of this attribute can be modified by an ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET DDL_REPLICATION_LEVEL=3;
Values set by ALTER SESSION
override the value set by this attribute.
For examples of altering an active standby pair, see "Altering an Active Standby Pair" in the Oracle TimesTen In-Memory Database Replication Guide.
To learn more about replicating DDL, see "Making DDL changes in an active standby pair" in the Oracle TimesTen In-Memory Database Replication Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set DDLReplicationLevel
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
DDLReplicationLevel |
1 - Replicates ALTER TABLE ADD or DROP COLUMN to the standby database. Does not replicate CREATE and DROP operations for tables, indexes, or synonyms to the standby database.
|
Windows ODBC Data Source Administrator | Not applicable |
Replication of DDL operations has these restrictions:
CREATE TABLE AS SELECT
statements are not replicated.
The CREATE INDEX
statement is replicated only when the index is created on an empty table.
To control whether a table or sequence is included in an active standby pair replication scheme at the time of creation, use the DDLReplicationAction
connection attribute.
Sequences with the CYCLE
attribute cannot be replicated.
Objects are replicated only when the receiving database is of a TimesTen release that supports that level of replication, and is configured for an active standby pair replication scheme. For example, replication of sequences (requiring DDL_REPLICATION_LEVEL=3
) to a database release prior to 11.2.2.7.0 is not supported. When DDLReplicationLevel
value is set to 3, both the active and standby master databases need to be TimesTen Release 11.2.2.7 or later. When DDL_REPLICATION_LEVEL=2
, the receiving database must be at least release 11.2.1.8.0 for replication of objects to be supported.
All restrictions for the UidPwdSet
built-in procedure apply.
When DDLReplicationLevel=1
or 2
, you cannot alter a table to add a NOT NULL
column to a table that is part of a replication scheme with the ALTER TABLE ... ADD COLUMN NOT NULL DEFAULT
statement. You must remove the table from the replication scheme first before you can add a NOT NULL
column to it. However, if DDLReplicationLevel=3
, then you can alter a table to add a NOT NULL
column to a table that is part of a replication scheme.
Enables an application to configure the level of diagnostics information generated by TimesTen for the connection. TimesTen diagnostics messages are warnings whose numbers lie within the range 20000 through 29999. Diagnostics
connection attribute values are integers.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Diagnostics
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Diagnostics | 0 - TimesTen does not generate diagnostic messages.
|
Windows ODBC Data Source Administrator | Not applicable |
By default, DurableCommits
is set to 0
. With this setting, TimesTen writes a log record to the file system when a transaction is committed, but the log record is not immediately written to disk. This reduces transaction execution time at the risk of losing some committed transactions if a failure occurs. When DurableCommits
is set to 1, TimesTen writes a log record to disk when the transaction is committed.
A connection can also call the ttDurableCommit
built-in procedure to do durable commits explicitly on selected transactions. A call to ttDurableCommit
flushes the log buffer to disk. The log buffer is shared among all connections and contains log records from transactions of all connections.
Log records are continually copied from the file system to disk. You can use LogFlushMethod
to control when the file system is synchronized with the disk.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set DurableCommits
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
DurableCommits |
0 (default) - TimesTen does not write the transaction log to disk on transaction commit.
|
Windows ODBC Data Source Administrator | Not applicable |
This attribute allows the application to control whether TimesTen shared memory should be included in application core dumps, and which portions of that memory should be included.
If multiple connections exist from a single application process to a single TimesTen database, the IncludeInCore
value of the most recent connection of the process determines the parts of the core file to dump.
For Client/Server connections, the setting is passed to TimesTen Server, which passes it on to the direct driver.
TimesTen daemons always dump everything.
The settings noted below are additive. For example, set IncludeInCore
to 3 (1+2) for DB header and other fixed allocations plus perm space. Set it to 15 (1+2+4+8) for DB header and other fixed allocations plus perm space, temp space, and log buffer.
ADMIN
privilege is required to include the DB header and other fixed allocations.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set IncludeInCore
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
IncludeInCore |
0 - Exclude the shared memory associated with this database connection from any core files.
2 - Include perm space from this database in core files.
The default value is 255. |
Windows ODBC Data Source Administrator | N/A |
By default, TimesTen uses read committed isolation. The Isolation attribute specifies the initial transaction isolation level for the connection. For a description of the isolation levels, see "Concurrency control through isolation and locking" in Oracle TimesTen In-Memory Database Operations Guide.
The value can be modified by an ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET ISOLATION_LEVEL=serializable;
CREATE CACHE GROUP
, ALTER CACHE GROUP
and DROP CACHE GROUP
statements are not supported in serializable isolation mode.
If the passthrough or the propagate TimesTen Cache feature is used, the TimesTen isolation level setting is inherited by the Oracle session. TimesTen serializable mode is mapped to Oracle's serializable mode. TimesTen read committed mode is mapped to Oracle's read committed mode. For more details on the passthrough attribute, see "PassThrough".
With PassThrough
set to 3, you must use an ALTER SESSION
statement to permanently modify the isolation level on the Oracle database connection. For example on a connection to the DSN repdb1_181
:
Call ttIsql
and connect to the DSN
with PassThrough
level 3:
% ttIsql; Command> connect "dsn=repdb1_181;passthrough=3"; Connection successful:. . .PassThrough=3; <default setting Autocommit=1>
Turn off AutoCommit
:
Command> autocommit=0;
Temporarily change the PassThrough
level to 0
:
Command> passthrough=0;
Alter the isolation level to serializable:
Command> prepare 1 ALTER SESSION SET ISOLATION_LEVEL=serializable; commit; exec=1;
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout. Only Isolation=1
is supported in TimesTen Scaleout.
Set Isolation
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Isolation |
0 - Connects to database in serializable isolation mode.
|
Windows ODBC Data Source Administrator | Not applicable |
By default, TimesTen enables row-level locking for maximum concurrency. With row-level locking, transactions usually obtain locks on the individual rows that they access, although a transaction may obtain a lock on an entire table if TimesTen determines that doing so would result in better performance. Row-level locking is the best choice for most applications, as it provides the finest granularity of concurrency control. To use row-level locking, applications must set the LockLevel
connection attribute to 0 (the default value). To cache Oracle database tables, you must set row-level locking. To CREATE
, DROP
, or ALTER
a user, you can only use row-level locking and thus, the lock level must be set to 0 before you can perform any of these operations.
To give every transaction in this connection exclusive access to the database, you can enable database-level locking by setting the LockLevel
attribute to 1. Doing so may improve performance for some applications.
A connection can change the desired lock level at any time by calling the ttLockLevel
built-in procedure. Connections can also wait for unavailable locks by calling the ttLockWait
built-in procedure. Different connections can coexist with different levels of locking, but the presence of even one connection doing database-level locking leads to loss of concurrency. To display a list of all locks on a particular database you can use the ttXactAdmin
utility.
When using PL/SQL in your applications, set LockLevel
=0 and selectively change to database level locking for specific transactions that require that level of locking by using the ttLockLevel
built-in procedure.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LockLevel
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LockLevel |
0 (default) - Transactions access the database using row-level locking.
|
Windows ODBC Data Source Administrator | Not applicable |
Enables an application to configure the lock wait interval for the connection. The lock wait interval is the number of seconds to wait for a lock when there is contention on it. Sub-second LockWait
values significant to tenths of a second can be specified using decimal format for the number of seconds. For example:
LockWait = 0.1
results in a lock wait of one tenth of a second.
LockWait
can be set to any value between 0 and 1,000,000 inclusive to a precision of tenths of a second. The default is 10
seconds:
LockWait = 10.0
Actual lock wait response time is imprecise and can be exceeded by up to one tenth of a second, due to the scheduling of the agent that detects timeouts. This imprecision does not apply to zero second timeouts, which are always reported immediately.
The number of connections to a database can impact the time needed to resolve lock contentions. If you anticipate having many connections to the database, increase the lock wait interval.
A connection can change the lock wait interval at any time by calling the
built-in procedure.
To display a list of all locks on a particular database you can use the TimesTen utility ttXactAdmin
.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set LockWait
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
LockWait |
s - Indicates the number of seconds to wait for locking conflict resolution before timing out. The default is 10 seconds. |
Windows ODBC Data Source Administrator | Not applicable |
The OptimizerHint
connection attribute establishes the connection's optimizer hint defaults. They can be different than the system defaults. The optimizer hints set with this connection attribute are set for every SQL statement in the user application.
The value of this attribute is a string of the same format as the statement level optimizer hints, but without the delimiters *+
, */
and -+
. The string can only contain the optimizer hint names. It cannot be mixed with other hint strings or comments.
The order of precedence for optimizer hints is statement level hints, transaction level hints and lastly hints set by this connection attribute.
For client/server applications, the attribute set by the client connection takes precedence over server DSN settings of this attribute.
Some symbols, such as semi-colons (;
) are not accepted in attribute values. For hints where the parameter might contain a semi-colon, multiple hints of the same name are combined into one hint. For example, to express:
TT_INDEX (t1,i1, 0; t2, i2,0)
use
TT_INDEX (t1,i1,0) TT_INDEX (t2, i2,0 )
To combine multiple hints at the connection level, you must enter them in the same line.
For a list of optimizer hints supported as values to this attribute, see "Statement level optimizer hints" in the Oracle TimesTen In-Memory Database SQL Reference.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set OptimizerHint
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
OptimizerHint |
A string specifying optimizer hints and their values. The maximum length of the string is 512. |
Windows ODBC Data Source Administrator | Not applicable |
Indicates the threshold percentage at which TimesTen issues out-of-memory warnings for the permanent partition of the database's memory. The database is considered no longer out of permanent memory if it falls 10% below this threshold. An application must call the built-in procedure ttWarnOnLowMemory
to receive out-of-memory warnings.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PermWarnThreshold
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PermWarnThreshold |
p - Percentage at which TimesTen should issue out-of-memory warnings. Default is 90 . |
Windows ODBC Data Source Administrator | Not applicable |
When multiple connections execute the same command, they access common command structures controlled by a single command lock. To avoid sharing their commands and possibly placing contention on the lock, you can use PrivateCommands
. This gives you better scaling at the cost of increased temporary space usage.
By default, the PrivateCommands
is turned off and commands are shared.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PrivateCommands
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PrivateCommands |
0 (default) - Commands are shared with other connections.
|
Windows ODBC Data Source Administrator | Not applicable |
If there are many copies of the same command, all of them are invalidated by a DDL or statistics change. Reprepare of these multiple copies takes longer when PrivateCommands
= 1. With more commands DDL execution can take slightly longer.
When using the PrivateCommands
attribute, memory consumption can increase considerably if the attribute is not used cautiously. For example, if PrivateCommands
=1 for an application that has 100 connections with 100 commands, there are 10,000 commands in the system: one private command for each connection.
The PWDCrypt
contains an encrypted version of the corresponding PWD
value. The value for PWD
is stored in clear text, which does not allow special characters, in the .odbc.ini
file on UNIX and Linux systems and in the Windows Registry on Windows. Any users who have access to the .odbc.ini
file or Windows Registry can view the value for this attribute. The PWDCrypt
attribute enables special characters, is case sensitive and contains the value of the encrypted password.
For security reasons, the PWDCrypt
attribute should only be placed in User DSNs or user private ODBCINI
files. The presence of the PWDCrypt
in System DSNs enables any user to use the PWDCrypt
value to connect to TimesTen, even though they have no knowledge of the cleartext password.
To generate the value for this attribute, run the ttUser
utility.
If PWD
and PWDCrypt
are both supplied, TimesTen uses the value of the PWD
attribute. See "UID and PWD".
TimesTen does not store the value of the PWD
attribute anywhere in the TimesTen system.
See "Required user authentication for utilities" in the description of "UID and PWD" for details about the treatment of passwords when using utilities that require specific privileges.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PWDCrypt
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PWDCrypt |
Enter the value generated by the ttUser utility. |
Windows ODBC Data Source Administrator | PWDCrypt field on the Oracle TimesTen Client DSN Setup dialog | Enter the value generated by the ttUser utility. |
Use this attribute to write a warning to the daemon log when the execution time of a SQL statement exceeds the specified value. You cannot set a query threshold for a SQL statement that is executed by the cache agent. The value of QueryThreshold
applies to all connections. It applies to all SQL statements except those executed by the replication agent or the cache agent.
The value of this attribute can be any integer equal to or greater than 0. The default value is 0
. A value of 0
indicates that no warning is issued. The unit is seconds.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set QueryThreshold
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
QueryThreshold |
A nonnegative integer. Default is 0 and indicates that TimesTen does not return a warning. |
Windows ODBC Data Source Administrator | Not applicable |
When managing track-based parallel replication, you can assign a connection to a replication track. All transactions issued by the connection are assigned to this track, unless the track is altered.
To start track-based parallel replication you must set a value for the ReplicationParallelism
attribute, specifying the number of replication tracks to be applied in parallel. You must also set ReplicationApplyOrdering
to 2.
The Track_ID
column of the TTREP.REPPEERS
system table (described in Oracle TimesTen In-Memory Database System Tables and Views Reference) shows the track associated with the connection.
You can use the ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference, to assign or change the value of this attribute within a session. For example:
ALTER SESSION SET REPLICATION_TRACK=4;
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set ReplicationTrack
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ReplicationTrack |
n - An integer between 1 and 64 that specifies the replication track to be used by transactions issued by the connection. |
Windows ODBC Data Source Administrator | Not applicable |
Use this attribute to specify the time limit in seconds within which the database should execute SQL statements.
This attribute does not stop TimesTen Cache operations that are being processed on an Oracle database. This includes passthrough statements, flushing, manual loading, manual refreshing, synchronous writethrough, and propagating.
Both SQLQueryTimeout
and SQLQueryTimeoutMSec
attributes are internally mapped to one timeout value in milliseconds. If different values are specified for these attributes, only one value is retained.
For more details, see "Choose SQL and PL/SQL timeout values" in the Oracle TimesTen In-Memory Database Operations Guide.
Note:
When SQL query timeouts are used (SQLQueryTimeout
or SQLQueryTimeoutMsec
), TimesTen behavior is on a best-effort basis. It is not possible to guarantee that the timeout will actually occur within the specified time.
SQL query timeouts are honored during dynamic load unless the dynamic load requires a new connection to the Oracle database, in which case the connection is allowed to complete. If the connection completes successfully but the dynamic load times out, the connection will be retained.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set SQLQueryTimeout
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
SQLQueryTimeout |
n - Time limit in seconds for which the database should execute SQL queries. The value of n can be any integer equal to or greater than 0. The default value is 0 . A value of 0 indicates that the query does not time out. |
Windows ODBC Data Source Administrator | Not applicable |
Use this attribute to specify the time limit in milliseconds within which the database should execute SQL statements.
This attribute does not stop TimesTen Cache operations that are being processed on an Oracle database. This includes passthrough statements, flushing, manual loading, manual refreshing, synchronous writethrough, and propagating.
Both SQLQueryTimeout
and SQLQueryTimeoutMsec
attributes are internally mapped to one timeout value in milliseconds. If different values are specified for these attributes, only one value is retained.
For more details, see "Choose SQL and PL/SQL timeout values" in the Oracle TimesTen In-Memory Database Operations Guide.
Notes:
When SQL query timeouts are used (SQLQueryTimeout
or SQLQueryTimeoutMsec
), TimesTen behavior is on a best-effort basis. It is not possible to guarantee that the timeout will actually occur within the specified time.
SQL query timeouts are honored during dynamic load unless the dynamic load requires a new connection to the Oracle database, in which case the connection is allowed to complete. If the connection completes successfully but the dynamic load times out, the connection will be retained.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set SQLQueryTimeoutMsec
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
SQLQueryTimeoutMSec |
n - Time limit in milliseconds for which the database should execute SQL queries. The value of n can be any integer equal to or greater than 0. The default value is 0 . A value of 0 indicates that the query does not time out. |
Windows ODBC Data Source Administrator | Not applicable |
Indicates the threshold percentage at which TimesTen issues out-of-memory warnings for the temporary partition of the database's memory. The database is considered no longer out of temporary memory if it falls 10% below this threshold. An application must call the built-in procedure ttWarnOnLowMemory
to receive out-of-memory warnings. See "ttWarnOnLowMemory".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TempWarnThreshold
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TempWarnThreshold |
p - Percentage at which warning should be issued. Default is 90 . |
Windows ODBC Data Source Administrator | Not applicable |
A user ID and password must be provided by a user who is identified internally to TimesTen. Alternatively, an encrypted password can be supplied using the PWDCrypt
attribute. Some TimesTen operations prompt for the UID
and PWD
of the user performing the operation.
For TimesTen client/server applications, specify UID
and PWD
either in the Client DSN configuration or in the connection string. The UID
and PWD
values specified in a connection string take precedence over the values specified in the Client DSN configuration.
Generally, when no UID connection attribute is given, the UID is assumed to be the user name identified by the operating system, and TimesTen does not prompt for a password.
When caching Oracle database tables, PWD
specifies the TimesTen password while OraclePWD
specifies the Oracle password.
Required user authentication for utilities
All utilities that require a password prompt for one.
If a UID
connection attribute is given but no PWD
attribute is given, either through a connection string or in the ODBCINI
file for the specified DSN, TimesTen prompts for a password. When explicitly prompted, input is not displayed on the command line.
A password given on the command line, before TimesTen prompts for the password, is visible to the ps
command, so use of the PWD
connection attribute is not recommended in the first call to the utility. For example, the following usage is not recommended:
% ttIsql -connStr "DSN=mydsn;UID=terry;PWD=secret";
Generally, when no UID
connection attribute is given, the UID
is assumed to be the user name identified by the operating system, and TimesTen does not prompt for a password.
When a utility accepts a DSN, connection string or database path as a parameter, specify the value at the end of the command line.
Usage in TimesTen Scaleout and TimesTen Classic
These attributes are supported in TimesTen Classic.
These attributes are supported in TimesTen Scaleout.
Set UID
and PWD
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
UID |
Character string specifying the user ID. |
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PWD |
Character string specifying the password that corresponds to the user ID. |
Windows ODBC Data Source Administrator | User ID and Password fields on the Oracle TimesTen Client DSN Setup dialog | Character string specifying the user ID. |
When an application requests a connection to a TimesTen database and the connection is not possible (perhaps during concurrent loading/recovery of a database), TimesTen normally waits for completion of the conflicting connection. In some cases, it can take some time for an application to connect to a database. If the WaitForConnect
attribute is off and the database is not immediately accessible, TimesTen returns immediately an error. For a description of the error, look for the error message number in "Warnings and Errors" in Oracle TimesTen In-Memory Database Error Messages and SNMP Traps.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set WaitForConnect
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
WaitForConnect |
0 - Does not wait if connection to database fails.
|
Windows ODBC Data Source Administrator | Not applicable |
NLS connection attributes are set by each connection and persist for the duration of the connection. These attributes control the globalization behaviors of the database. NLS general connection attributes are listed Table 2-4, "NLS general connection attributes" and described in detail in this section.
You can use the ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference, to change NLS parameters to override the values that are assigned to these attributes at connection time.
ConnectionCharacterSet
is also available as a Client connection attribute.
This attribute specifies the character encoding for the connection, which can be different from the database character set. This can be useful when you have multiple connections to a database and one or more of those connections requires a character set that differs from that specified in the database.
The connection character set determines the character set in which data is displayed or presented.
Generally, you should choose a connection character set that matches your terminal settings or data source. Your database character set should be chosen based on the data requirements. For example: Do you have data in Unicode or is your data in Japanese on UNIX or Linux (EUC) or Windows (SJIS)?
When the database and connection character sets differ, TimesTen performs data conversion internally based on the connection character set. If the connection and database character sets are the same, TimesTen does not need to convert or interpret the data set. Best performance occurs when connection and database character sets match, since no conversion is required.
Parameters and SQL query text sent to the connect should be in the connection character set. Results and error messages returned by the connection are returned in the connection character set.
This attribute accepts the same values used for the DatabaseCharacterSet
. For a list of supported character set names, see "Supported character sets".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set ConnectionCharacterSet
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
ConnectionCharacterSet |
The default value for ConnectionCharacterSet is US7ASCII . |
Windows ODBC Data Source Administrator | Connection CharacterSet list field on the Oracle TimesTen Client DSN Setup dialog | The default value for ConnectionCharacterSet is US7ASCII . |
TimesTen uses the NLS_LENGTH_SEMANTICS
attribute to set the default length semantics configuration. Length semantics determines how the length of a character string is determined. The length can be treated as a sequence of characters or a sequence of bytes.
NLS_LENGTH_SEMANTICS
can be modified by an ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set NLS_LENGTH_SEMANTICS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
NLS_LENGTH_ SEMANTICS |
Specify either BYTE (default) or CHAR . |
Windows ODBC Data Source Administrator | Not applicable |
The NLS_NCHAR_CONV_EXCP
attribute determines whether an error is reported when there is data loss during an implicit or explicit character type conversion between NCHAR
/NVARCHAR2
data and CHAR
/VARCHAR2
data. A replacement character is substituted for characters that cannot be converted.
Implicit and explicit conversions between CHAR
and NCHAR
are supported.
NLS_NCHAR_CONV_EXCP
can be modified by an ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set NLS_NCHAR_CONV_EXCP
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
NLS_NCHAR_CONV_EXCP |
0 (default) - Errors are not reported when there is a data loss during character type conversion.
|
Windows ODBC Data Source Administrator | Not applicable |
The NLS_SORT
attribute indicates which collating sequence to use for linguistic comparisons. It accepts the values listed in "Supported Linguistic Sorts." All these values can be modified to do case-insensitive sorts by appending _CI
to the value. To perform accent-insensitive and case-insensitive sorts, append _AI
to the value.
For materialized views and cache groups, TimesTen recommends that you explicitly specify the collating sequence using the NLSSORT
SQL function rather than using this attribute in the connection string or DSN definition.
Operations involving character comparisons support linguistic case-sensitive collating sequences. Case-insensitive sorts may affect DISTINCT
value interpretation.
NLS_SORT
may affect many operations. The supported operations that are sensitive to collating sequence are:
MIN
, MAX
BETWEEN
=
, <>
, >
, >=
, <
, <=
DISTINCT
CASE
GROUP BY
HAVING
ORDER BY
IN
LIKE
NLS_SORT
settings other than BINARY
may have significant performance impact on character operations.
NLS_SORT
can be modified by an ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference.
Note:
Primary key indexes are always based on theBINARY
collating sequence. Use of non-BINARY NLS_SORT
equality searches cannot use the primary key indexUsage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set NLS_SORT
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
NLS_SORT |
Specify the linguistic sort sequence or BINARY (default). |
Windows ODBC Data Source Administrator | Not applicable |
The tables in this section list the supported values for the NLS_SORT
general connection attribute and the NLS_SORT
SQL function.
Basic name | Extended name |
---|---|
ARABIC |
- |
ARABIC_MATCH |
- |
ARABIC_ABJ_SORT |
- |
ARABIC_ABJ_MATCH |
- |
ASCII7 |
- |
AZERBAIJANI |
XAZERBAIJANI |
BENGALI |
- |
BIG5 |
- |
BINARY |
- |
BULGARIAN |
- |
CANADIAN FRENCH |
- |
CATALAN |
XCATALAN |
CROATIAN |
XCROATIAN |
CZECH |
XCZECH |
CZECH_PUNCTUATION |
XCZECH_PUNCTUATION |
DANISH |
XDANISH |
DUTCH |
XDUTCH |
EBCDIC |
- |
EEC_EURO |
- |
EEC_EUROPA3 |
- |
ESTONIAN |
- |
FINNISH |
- |
FRENCH |
XFRENCH |
GERMAN |
XGERMAN |
GERMAN_DIN |
XGERMAN_DIN |
GBK |
- |
GREEK |
- |
HEBREW |
- |
HKSCS |
- |
HUNGARIAN |
XHUNGARIAN |
ICELANDIC |
- |
INDONESIAN |
- |
ITALIAN |
- |
LATIN |
- |
LATVIAN |
- |
LITHUANIAN |
- |
MALAY |
- |
NORWEGIAN |
- |
POLISH |
- |
PUNCTUATION |
XPUNCTUATION |
ROMANIAN |
- |
RUSSIAN |
- |
SLOVAK |
XSLOVAK |
SLOVENIAN |
XSLOVENIAN |
SPANISH |
XSPANISH |
SWEDISH |
- |
SWISS |
XSWISS |
THAI_DICTIONARY |
- |
TURKISH |
XTURKISH |
UKRAINIAN |
- |
UNICODE_BINARY |
- |
VIETNAMESE |
- |
WEST_EUROPEAN |
XWEST_EUROPEAN |
Sort name | Description |
---|---|
CANADIAN_M |
Canadian French sort supports reverse secondary, special expanding characters. |
DANISH_M |
Danish sort supports sorting uppercase characters before lowercase characters. |
FRENCH_M |
French sort supports reverse sort for secondary. |
GENERIC_M |
Generic sorting order which is based on ISO14651 and Unicode canonical equivalence rules but excluding compatible equivalence rules. |
JAPANESE_M |
Japanese sort supports SJIS character set order and EUC characters which are not included in SJIS. |
KOREAN_M |
Korean sort Hangul characters are based on Unicode binary order. Hanja characters based on pronunciation order. All Hangul characters are before Hanja characters. |
SPANISH_M |
Traditional Spanish sort supports special contracting characters. |
THAI_M |
Thai sort supports swap characters for some vowels and consonants. |
SCHINESE_RADICAL_M |
Simplified Chinese sort is based on radical as primary order and number of strokes order as secondary order. |
SCHINESE_STROKE_M |
Simplified Chinese sort uses number of strokes as primary order and radical as secondary order. |
SCHINESE_PINYIN_M |
Simplified Chinese Pinyin sorting order. |
TCHINESE_RADICAL_M |
Traditional Chinese sort based on radical as primary order and number of strokes order as secondary order. |
TCHINESE_STROKE_M |
Traditional Chinese sort uses number of strokes as primary order and radical as secondary order. It supports supplementary characters. |
PL/SQL connection attributes are set by each connection and persist for the duration of the connection. These attributes control the behaviors of the database. PL/SQL first connection attributes are listed Table 2-5, "PL/SQL first connection attributes" and described in detail in this section.
Use of PL/SQL requires a shared memory segment. This shared memory contains recently-executed PL/SQL code, shared package state, and metadata associated with the operation of PL/SQL. This shared memory segment is separate from the one containing the TimesTen database.
This attribute determines the virtual address at which this shared memory segment is loaded into each process that uses the TimesTen direct drivers. This memory address must be identical in each process using TimesTen. You must specify the value as a hexadecimal address.
If you do not specify a value for PLSQL_MEMORY_ADDRESS
, TimesTen uses a platform-dependent default value.
The default values for each platform are designed to:
Maximize the amount of virtual space for your TimesTen database and for your applications.
Minimize the fragmentation of the virtual address space.
Avoid conflicts with other uses of virtual address space. -64
The platform specific default memory addresses are:
Operating system | Address |
---|---|
Linux x86-64 | 0000005000000000 |
AIX | 06ffffff00000000 |
Windows | 000000005b8c0000 |
HP-UX | 0 |
Some things to consider when setting this attribute are:
If applications simultaneously connect to multiple TimesTen databases in direct mode, then each database must use a different value for PLSQL_MEMORY_ADDRESS
.
The value of this attribute is stored persistently by TimesTen. The persistent attribute value is specified in situations when the database is loaded automatically by TimesTen. For example, the database is automatically loaded if RamPolicy
for the database is set to 1.
If the PL/SQL shared memory cannot be mapped at the appropriate address, TimesTen returns an error and the connection to the database fails.
The memory segment size is determined by the value of PLSQL_MEMORY_SIZE
.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_MEMORY_ADDRESS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_MEMORY_ADDRESS |
A hexidecimal value that indicates the memory address for PL/SQL process. |
Windows ODBC Data Source Administrator | Not applicable |
Use of PL/SQL requires a shared memory segment. This attribute determines the size in megabytes of the shared memory segment used by PL/SQL. All connections share this memory segment.
This shared memory contains recently-executed PL/SQL code, the shared package state, and metadata associated with the operation of PL/SQL. This shared memory segment is separate from the one containing the TimesTen database.
Some things to consider when setting this attribute are:
The value of this attribute is stored persistently by TimesTen. The persistent attribute value is specified in situations when the database is loaded automatically by TimesTen. For example, the database is automatically loaded if RamPolicy for the database is set to 1.
For most PL/SQL users, the default memory size should be an adequate amount of memory. For databases that make extensive use of PL/SQL, specify a larger memory size. If the memory space is exhausted, ORA-4031
errors may occur during PL/SQL execution.
The address of the memory segment is determined by the value of PLSQL_MEMORY_ADDRESS
.
There is both a fixed and per connection overhead allocated from the PL/SQL segment, even if you do not use PL/SQL. The minimum fixed memory allocated is approximately 1500 KB. Additionally, approximately 40 KB of memory is allocated per connection. Thus, you can compute an estimated minimum memory setting needed as 1500 KB plus (number_of_connections
* 40
). If the application uses PL/SQL, we recommend that you allocate twice the estimated minimum required memory for this segment. If the application does not use PL/SQL, you can allocate less than twice the estimated minimum required memory.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_MEMORY_SIZE
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_MEMORY_SIZE |
Specify a positive integer greater than 2 representing the size in MB of the shared memory segment in megabytes. The default size is 128 MB. |
Windows ODBC Data Source Administrator | Not applicable |
This attribute specifies the maximum number of PL/SQL cursors that can be open in a session at one time. Use this to prevent a session from opening an excessive number of cursors. Default is 50 PL/SQL cursors.
Updating the value of this attribute takes effect on the next connection, not the current connection.
If you decrease the value and the number of open cursors currently exceeds or equals the new setting, no new cursors can be opened until the total number of open cursors is less than the new setting (i.e., some of the currently open cursors have to close).
A value of 0
indicates no PL/SQL cursors can be open. (But if there are cached PL/SQL cursors that contain any PL/SQL code, they could still be executed.)
Note:
This attribute has the same functionality asOPEN_CURSORS
in Oracle Database.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_OPEN_CURSORS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_OPEN_CURSORS |
A positive integer from 0 to 65535 representing the number of cursors that can be open in one session at one time.
The default value is |
Windows ODBC Data Source Administrator | N/A |
PL/SQL general connection attributes are set by each connection and persist for the duration of the connection. These attributes control the behaviors of the database. PL/SQL general connection attributes are listed in Table 2-6, "PL/SQL general connection attributes" and described in detail in this section.
You can use the ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference, to change PL/SQL parameters to override the values that are assigned to the PL/SQL general connection attributes at connection time.
PLSCOPE_SETTINGS
controls whether the PL/SQL compiler generates cross-reference information. Either all or no cross-references are generated. Possible values are IDENTIFIERS:NONE
or IDENTIFIERS:ALL
.
The PLSCOPE_SETTINGS
connection attribute determines the initial value of this attribute within a session. The value can be modified by an ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET PLSCOPE_STTINGS = 'IDENTIFIERS:ALL' ;
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set PLSCOPE_SETTINGS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
PLSCOPE_SETTINGS |
IDENTIFIERS:NONE (default)
|
Windows ODBC Data Source Administrator | Not applicable |
This attribute sets directives to control conditional compilation of PL/SQL units, which enables you to customize the functionality of a PL/SQL program depending on conditions that are checked. This is especially useful when applications are deployed to multiple database environments. Possible uses include activating debugging or tracing features, or basing functionality on the version of the database.
Use this format:
PLSQL_CCFLAGS = 'v1:c1,v2:c2,...,vn:cn'
v1
has the form of an unquoted PL/SQL identifier. It is unrestricted and can be a reserved word or a keyword. The text is insensitive to case. Each one is known as a flag or flag name. Each vi
can occur multiple times in the string, each occurrence can have a different flag value, and the flag values can be of different kinds.
c1
is one of the following: a PL/SQL boolean literal, a PLS_INTEGER
literal, or the literal NULL
. The text is insensitive to case. Each one is known as a flag value and corresponds to a flag name.
You can use the ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference, to change this attribute within a session:
ALTER SESSION SET PLSQL_CCFLAGS = 'v1:c1,v2:c2,...,vn:cn';
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_CCFLAGS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_CCFLAGS |
'A string literal with this format:
Default: null |
Windows ODBC Data Source Administrator | Not applicable |
This attribute specifies the maximum amount of process heap memory in megabytes that PL/SQL can use for the connection in which it is set.
Some things to consider when setting this attribute are:
PL/SQL does not allocate this memory until or unless it is needed. Many PL/SQL programs require only a small amount of memory. How you write your application can determine memory requirements. For example, using large VARRAYs
in PL/SQL code can require a lot of memory.
If you attempt to allocate more memory than allowed, TimesTen returns an error.
The value can be modified with the ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET PLSQL_CONN_MEM_LIMIT = 100;
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_CONN_MEM_LIMIT
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_CONN_MEM_LIMIT |
An integer value in MB. Default value is 100 . A setting of 0 means no limit. |
Windows ODBC Data Source Administrator | Not applicable |
The amount of space consumed by PL/SQL variables is roughly what you might expect comparable variables to consume in other programming languages. As an example, consider a large array of strings:
type chararr is table of varchar2(32767) index by binary_integer; big_array chararr;
If 100,000 strings of 100 bytes each are placed into such an array, approximately 12 megabytes of memory is consumed.
Memory consumed by variables in PL/SQL blocks is used while the block executes, then is released. Memory consumed by variables in PL/SQL package specifications or bodies (not within a procedure or function) is used for the lifetime of the package. Memory consumed by variables in a PL/SQL procedure or function, including one defined within a package, is used for the lifetime of the procedure or function. However, in all cases, memory freed by PL/SQL is not returned to the operating system. Instead, it is kept by PL/SQL and reused by future PL/SQL invocations. The memory is freed when the application disconnects from TimesTen.
This attribute specifies the optimization level to be used to compile PL/SQL library units. The higher the setting of this parameter, the more effort the compiler makes to optimize PL/SQL library units. Possible values are 0, 1, 2, or 3.
The PLSQL_OPTIMIZE_LEVEL
connection attribute determines the initial value of this attribute within a session. The value can be modified by an ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. For example:
ALTER SESSION SET PLSQL_OPTIMIZE_LEVEL = 2;
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_OPTIMIZE_LEVEL
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_OPTIMIZE_LEVEL |
The default value is 2 . |
Windows ODBC Data Source Administrator | Not applicable |
This attribute specifies the number of session cursors to cache. A user may adjust the setting to free up space not currently needed in the cache.
PLSQL_SESSION_CACHED_CURSORS
can be modified by an ALTER SESSION
SQL statement, described in Oracle TimesTen In-Memory Database SQL Reference.
ALTER SESSION SET PLSQL_SESSION_CACHED_CURSORS=25;
Note:
This attribute has the same functionality asSESSION_CACHED_CURSORS
in Oracle Database.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_SESSION_CACHED_CURSORS
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_SESSION_CACHED_CURSORS |
A positive integer from 1 to 65535 representing the number of cursors to cache.
The default value is |
Windows ODBC Data Source Administrator | N/A |
This attribute controls how long (in seconds) PL/SQL program units, including PL/SQL procedures, anonymous blocks and functions, are allowed to run before being automatically terminated.
This value can be modified with an ALTER SESSION
statement, described in Oracle TimesTen In-Memory Database SQL Reference. If this value is modified through ALTER SESSION
, the new value impacts any PL/SQL program units that are currently running. For example:
ALTER SESSION SET PLSQL_TIMEOUT = 10;
Notes:
See "Choose SQL and PL/SQL timeout values" in Oracle TimesTen In-Memory Database Operations Guide for information about the relationship between TTC_Timeout
, SQLQueryTimeout
, and PLSQL_TIMEOUT
.
The frequency with which PL/SQL programs check execution time against this timeout value is variable. It is possible for programs to run significantly longer than the timeout value before being terminated.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set PLSQL_TIMEOUT
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
PLSQL_TIMEOUT |
A positive integer representing the number of seconds for the timeout value.
A value of The default value is |
Windows ODBC Data Source Administrator | Not applicable |
TimesTen Cache first connection attributes are used only when you are using the TimesTen Cache product. TimesTen Cache first connection attributes are listed in Table 2-7, "TimesTen Cache first connection attributes" and described in detail in this section.
Determines whether asynchronous writethrough propagation uses the PL/SQL execution method or SQL array execution method to apply changes to the Oracle database server.
By default, asynchronous writethrough (AWT) uses PL/SQL execution method, CacheAWTMethod=1
. AWT bundles all pending operations into a single PL/SQL collection that is sent to the Oracle database server to be executed. This method can improve AWT throughput when there are mixed transactions and network latency between TimesTen and the Oracle database server.
The SQL array execution to apply changes within TimesTen to the Oracle database works well when the same type of operation is repeated. For example, array execution is very efficient when a user does an update that affects several rows of the table. Updates are grouped together and sent to the Oracle database server in one batch.
PL/SQL execution method transparently falls back to array execution mode temporarily when it encounters one of the following:
A statement that is over 32761 bytes in length.
A statement that references a column of type BINARY FLOAT
, BINARY DOUBLE
and VARCHAR
of length greater than 4000 bytes.
Specify the SQL execution method, CacheAWTMethod=0
, if any AWT cache group contains a VARBINARY
column.
The SYSTEMSTATS
table contains information about the number of times the execution method temporarily falls back to SQL array execution.
Notes:
This attribute can also be set through the ttDBConfig
built-in procedure, which overrides the connection attribute setting. See "ttDBConfig".
Use the same AWT execution method on all TimesTen nodes in any active standby pair replication scheme.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set CacheAWTMethod
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
CacheAWTMethod |
0 - Use SQL array execution method.
|
Windows ODBC Data Source Administrator | Not applicable |
TimesTen Cache connection attributes are used only when you are using the TimesTen Cache product. TimesTen Cache data store attributes are listed and described in detail in this section.
CacheAWTParallelism
indicates the number of threads that apply changes to the Oracle database. This attribute has a relationship to ReplicationParallelism
and ReplicationApplyOrdering
.
If you do not set this attribute or if you set it to the default value of 1, the number of threads that apply changes to the Oracle database is twice the setting for ReplicationParallelism
to the maximum value of 31.
If both ReplicationParallelism
and CacheAWTParallelism
attributes are set, the value set in CacheAWTParallelism
configures the number of threads used for parallel propagation. The setting for CacheAWTParallelism
determines the number of apply threads for parallel propagation and the setting for ReplicationParallelism
determines the number of threads for parallel replication.
CacheAWTParallelism
only has an affect when there are AWT cache groups.
To learn more about parallel AWT caching, see "Configuring parallel propagation to Oracle Database tables" in the Oracle TimesTen Application-Tier Database Cache User's Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set CacheAWTParallelism
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
CacheAWTParallelism |
n - An integer between 1 and 31 that indicates the number of threads that apply changes to the Oracle database. The default is 1 . |
Windows ODBC Data Source Administrator | Not applicable |
Enable the cache connection pool with the UseCacheConnPool
connection attribute.
The cache connection pool can only be initiated from client-server applications and is used only for dynamic loads initiated for dynamic read-only cache groups.
To learn more about the cache connection pool, see "Managing a cache connection pool to the Oracle database for dynamic load requests" in the Oracle TimesTen Application-Tier Database Cache User's Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set UseCacheConnPool
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
UseCacheConnPool |
2 - Enabled: For each statement that requires a dynamic load from the Oracle database, the connections to Oracle are released after the load completes and the connection is returned to the cache connection pool.
If a dynamic load is performed from a direct connection, the dynamic load proceeds as if the feature is not enabled.
|
Windows ODBC Data Source Administrator | N/A |
TimesTen Cache general connection attributes are used only when you are using the TimesTen Cache product. TimesTen Cache general connection attributes are listed in Table 2-9, "TimesTen Cache general connection attributes" and described in detail in this section.
This attribute enables or disables dynamic load of data from an Oracle database to a TimesTen dynamic cache group. By default, dynamic load of data from an Oracle database is enabled.
To enable or disable dynamic load at the statement level and temporarily override the setting of this attribute, set the DynamicLoadEnable
optimizer flag with the ttOptSetFlag
built-in procedure or using the statement level optimizer hint TT_DynamicLoadEnable
in a SQL statement.
Note:
The value of this attribute overrides the dynamic load behavior of all dynamic cache groups for the current connection to the database.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set DynamicLoadEnable
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
DynamicLoadEnable |
0 - Disables dynamic load of data from an Oracle database to TimesTen dynamic cache groups for the current connection.
|
Windows ODBC Data Source Administrator | Not applicable |
This attribute controls what happens when an application executes a SQL operation against a dynamic cache group and the SQL operation cannot use dynamic load.
With a value of 0, the SQL operation executes against whatever data is in the TimesTen cache tables and returns a result based on that data with no error indicated.
With a value of 1, any statement that cannot use dynamic load (even if it does not need dynamic load) fails with an error indicating that it is not dynamic load-compliant.
For more information on caching data from an Oracle database in a TimesTen cache group, see Oracle TimesTen Application-Tier Database Cache User's Guide.
Note:
To override the value of this attribute at the statement level, set theDynamicLoadErrorMode
optimizer flag with the ttOptSetFlag
built-in procedure or using the statement level optimizer hint TT_DynamicLoadErrorMode
in a SQL statement.
For details, see "Statement level optimizer hints" in the Oracle TimesTen In-Memory Database SQL Reference.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set DynamicLoadErrorMode
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
DynamicLoadErrorMode |
0 (default) - Statements execute against the cached data with no error.
|
Windows ODBC Data Source Administrator | Not applicable |
The TimesTen Cache uses the OracleNetServiceName
attribute.
This attribute identifies the Service Name for the Oracle instance.
To cache Oracle database tables and enable communication with the Oracle database, you must specify an Oracle Service Name.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set OracleNetServiceName
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
OracleNetServiceName |
Character string specifying the Oracle Service Name that is to be used as the Oracle ID. |
Windows ODBC Data Source Administrator | Not applicable |
The TimesTen Cache uses the OraclePWD
attribute to connect to the Oracle database to perform cache operations.
The Oracle database user has the same user name as the TimesTen cache manager user, whose user name is specified by UID
(and whose password on TimesTen is specified by PWD
). Hence, the value of this attribute is the password for the user specified by UID
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
This attribute must be set in the connection string. On Linux, suppose you have defined the following odbc.ini
file:
[myDSN] Datastore=/data/myDSN PermSize=128 DatabaseCharacterSet=AL32UTF8 ConnectionCharacterSet=AL32UTF8
Set OraclePWD
for user ttuser
by connecting to myDSN
as follows:
% ttisql Copyright (c) 1996-2011, Oracle. All rights reserved. Type ? or "help" for help, type "exit" to quit ttIsql. Command> connect "dsn=myDSN;OraclePWD=mypwd"; Connection successful: DSN=beta4;UID=ttuser;DataStore=/data/myDSN;DatabaseCharacterSet=AL32UTF8; ConnectionCharacterSet=AL32UTF8;PermSize=128; (Default setting AutoCommit=1)
On Windows, set OraclePWD
in the connection string in the same way that it is set on Linux.
The TimesTen Cache uses the PassThrough
attribute.
It specifies which SQL statements are executed only in the cache database and which SQL statements are passed through to the Oracle database. For more information about the TimesTen Cache, see Oracle TimesTen Application-Tier Database Cache User's Guide and "CREATE CACHE GROUP" in Oracle TimesTen In-Memory Database SQL Reference.
The execution of a prepared PassThrough
command assumes that the schema of dependent objects in the Oracle database has not changed since the prepare. If the schema has changed the PassThrough
command may cause unexpected results from the Oracle database.
When passing SQL statements through to the Oracle database, use only TimesTen supported data types in column definitions. If the specified data type is not supported in TimesTen, the passthrough statement fails.
For information on changing the isolation level on the Oracle database connection, when using this attribute, see "Isolation".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set PassThrough
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
PassThrough |
0 (default) - SQL statements are executed only on TimesTen.
|
Windows ODBC Data Source Administrator | Not applicable |
Certain restrictions must be considered when using the passthrough feature. They include:
If the PassThrough
attribute is set so that a query must be executed in the Oracle database, the query is sent to the Oracle database without any changes. If the query uses a synonym for a table in a cache group, then a synonym with the same name must be defined for the corresponding Oracle database table for the query to be successful.
In the case that a SQL statement that uses TimesTen only syntax is passed through to the Oracle database, TimesTen returns an error message that indicates the syntax is not supported in the Oracle database.
Execution of a prepared passthrough command assumes that the schema of dependent objects in the Oracle database have not changed after the prepare. If the schema has changed, unexpected results can occur.
TimesTen does not include a cache invalidation feature. TimesTen does not verify that the cached tables are up to date. When a query is syntactically correct in TimesTen and the cache contains all the tables referenced in the query, the query is executed in TimesTen regardless of whether the cache is up to date.
The passthrough of Oracle INSERT
, UPDATE
, or DELETE
operations depends on the setting of the PassThrough
attribute as described in the table above. TimesTen Cache cannot detect INSERT
, UPDATE
and DELETE
operations that are hidden in a trigger or stored procedure. Therefore, TimesTen cannot enforce the passthrough rule on hidden operations.
You cannot pass PL/SQL blocks through to the Oracle database.
The effects of a passthrough INSERT
, UPDATE
, or DELETE
operation on a read-only cache group are only seen after the transaction is committed and after the next autorefresh operation is completed.
There is no mechanism to detect or block updates on an Oracle database table that is cached in a TimesTen synchronous writethrough cache group. Whether the updates are made by statements passed through the cache or from other Oracle database applications, the changes are never reflected in TimesTen Cache.
Oracle Call Interface (OCI) does not support a mechanism to describe the binding type of the input parameters. Ensure that your application supplies the correct SQL types for passthrough statements. The ODBC driver converts the C and SQL types and presents the converted data and the SQL type code to TimesTen. TimesTen presents the information to OCI. The length of the input binding values is restricted to 4000 for LONG
and LONG RAW
types.
At all passthrough levels, passthrough execution of DDL statements does not result in commits on the TimesTen side.
A transaction that contains operations that are replicated with RETURN TWOSAFE
cannot have a PassThrough
setting greater than 0
. If PassThrough
is greater than 0
, an error is returned and the transaction must be rolled back.
When PassThrough
is set to 0
, 1
, or 2
, the following behavior occurs when a dynamic load condition exists:
A dynamic load can occur for a SELECT
operation on cache tables in any dynamic cache group type.
A dynamic load for an INSERT
, UPDATE
, or DELETE
operation can only occur on cached tables with dynamic asynchronous or synchronous writethrough cache groups.
Refer to "SQL Statements" in Oracle TimesTen In-Memory Database SQL Reference for details about the INSERT
, UPDATE
, DELETE
, and SELECT
statements.
This attribute enables you to enable or disable the installation of Transparent Application Failover (TAF) and Fast Application Notification (FAN) callbacks when using Oracle Real Application Clusters (Oracle RAC) with TimesTen Cache.
For more information about TimesTen Cache, see Oracle TimesTen Application-Tier Database Cache User's Guide and "CREATE CACHE GROUP" in Oracle TimesTen In-Memory Database SQL Reference.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set RACCallback
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
RACCallback |
0 - Do not install TAF and FAN callbacks.
|
Windows ODBC Data Source Administrator | Not applicable |
The TimesTen Cache uses the StandbyNetServiceName
attribute.
This attribute identifies the Service Name for the standby Oracle instance from an Oracle Active Data Guard environment.
To cache Oracle database tables and enable communication with the standby Oracle database, you must specify an Oracle Service Name.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported with TimesTen Scaleout.
Set StandbyNetServiceName
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
StandbyNetServiceName |
Character string specifying the Oracle Service Name that is to be used as the standby Oracle ID. |
Windows ODBC Data Source Administrator | Not applicable |
TimesTen Client connection attributes are used only when you are connecting to a TimesTen server from a TimesTen client application. TimesTen Client connection attributes are listed in Table 2-10, "TimesTen Client connection attributes" and described in detail in this section.
In addition to the attributes listed in this section, some database attributes and general connection attributes are also available for client connections or impact the behavior of the connection. These attributes are:
To view the value of a client attribute:
In ODBC 3.5, use the ODBC function SQLGetConnectAttr
. To learn more about this function, see "Attribute support for ODBC 3.5 SQLSetConnectAttr and SQLGetConnectAttr" in Oracle TimesTen In-Memory Database C Developer's Guide
In ODBC 2.5, use the ODBC function SQLGetConnectOption
. To learn more about this function, see "Option support for ODBC 2.5 SQLSetConnectOption and SQLGetConnectOption" section of the Oracle TimesTen In-Memory Database C Developer's Guide.
The CipherSuites
attribute lists the cipher suite or suites that can be used, depending also on the client setting. Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
, SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
, or both, comma-separated and in order of preference. There is no default setting.
You must set this attribute for both the client and the server. For TLS to be used, the server and client settings must include at least one common suite.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set CipherSuites
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
CipherSuites | Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 , SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 , or both, comma-separated and in order of preference |
Windows ODBC Data Source Administrator | CipherSuites field on the Oracle TimesTen Client DSN Setup dialog. | Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 , SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 , or both, comma-separated and in order of preference |
Identify the client server process with the ClientServer
connection attribute.
In a client/server environment, TimesTen can have multiple TimesTen child server processes to handle incoming requests from clients. You provide the ChildServer
connection attribute to identify a specific child server process for certain cache connection pool built-in procedures.
Each child server process is identified by a number assigned with the ChildServer=
n
connection attribute, where n
is a number ranging from 1 to the number of running child server processes. Once connected to the child server process, you can execute either the ttCacheConnPoolGet('current')
or ttCacheConnPoolApply
built-in procedures that are meant for a specific child server process.
To learn more about the ClientServer
connection attribute, see "Managing a cache connection pool to the Oracle database for dynamic load requests" in the Oracle TimesTen Application-Tier Database Cache User's Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set ClientServer
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
ClientServer |
ChildServer= n , where n is a number ranging from 1 to the number of running child server processes.
The default value for the |
Windows ODBC Data Source Administrator | Not applicable |
The Encryption
attribute specifies whether encryption is required or not for a client server connection.
You must set this attribute for both the client and the server. Cipher settings must be the same on both the client and server, in most cases.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set Encryption
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
Encryption |
|
Windows ODBC Data Source Administrator | Encryption field on the Oracle TimesTen Client DSN Setup dialog. |
|
The SSLClientAuthentication
attribute specifies whether SSL client authentication is required (setting of 1) or not (setting of 0, the default). With client authentication, the server validates an identity presented by the client, and requires an identity (public/private key) in the client wallet.
Regardless of the client authentication setting, server authentication is performed, where the client validates the server.
You must set this attribute for both the client and the server. Regardless of the client authentication setting, server authentication is performed, where the client validates the server.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set SSLClientAuthentication
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
SSLClientAuthentication |
1 - Client authentication is required
|
Windows ODBC Data Source Administrator | SSL Client Authentication field on the Oracle TimesTen Client DSN Setup dialog. | 1 - Client authentication is required
|
When connecting to a TimesTen database using the TimesTen Client and Server, the TimesTen Client requires the network address and the TCP port number of the computer running the TimesTen Server.
The default TCP/IP port number is assumed for TCP_Port
unless you specify a value in the TTC_Server
connection attribute, in the ODBC connection string, or in the logical server definition. See"TTC_Server or TTC_Server1" for more details.
If the TimesTen Server is listening on a non-default port number, you must provide the port number in one of the following ways:
If using TimesTen Classic, you can specify the port number within the logical server definition, which contains the network address and port number pair. See "Defining a logical server name" in Oracle TimesTen In-Memory Database Operations Guide for more information on defining a logical server.
You can specify the port number within the TTC_Server
connection attribute using:
TTC_SERVER=server_host_name/server_port;
You can specify the port number in the ODBC connection string.
"TTC_SERVER=server_host_name;TTC_SERVER_DSN=Server_DSN; TCP_PORT=server_port"
Or:
"DSN=Client_DSN;TCP_Port=server_port"
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TCP_Port
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs | TCP_Port |
Specify the port number where the Server is listening. |
Windows ODBC Data Source Administrator and UNIX and Linux systems ttconnect.ini file. See Creating and configuring a logical server name on Linux and UNIX in the Oracle TimesTen In-Memory Database Operations Guide for more details. |
TCP_Port on the Oracle TimesTen Logical Server Name Setup dialog. | Specify the port number where the Server is listening. |
For TimesTen Classic, TimesTen uses this attribute to specify the port number to use if an automatic failover occurs. (This is unnecessary for TimesTen Scaleout.) See the description of TCP_Port
for details on setting the value of this attribute and associated attributes.
The default TCP/IP port number is assumed for TCP_Port2
and TCP_Port
N
unless you specify a value in the appropriate TTC_Server
N
connection attribute, in the ODBC connection string, or in the logical server definition. See "TTC_Server or TTC_Server1" for more details.
Unspecified values for TCP_Port
N
inherit the value of TCP_PORT
(or TCP_PORT1
). For example, if TTC_Server2
is specified but TTC_Server_DSN2
and TCP_Port2
are not, then TTC_Server_DSN2
is set to the TTC_Server_DSN
value and TCP_Port2
is set to the TCP_Port
value.
See "Using automatic client failover" in Oracle TimesTen In-Memory Database Operations Guide for more information on automatic client failover.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TCP_Port2, TCP_PortN
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs | TCP_Port2, TCP_Port N |
Specify the failover port number where the Server should listen. |
Windows ODBC Data Source Administrator and UNIX and Linux systems ttconnect.ini file. See Creating and configuring a logical server name on Linux and UNIX in the Oracle TimesTen In-Memory Database Operations Guide for more details. |
Specify TCP_Port2, TCP_PortN in a connection string when also specifying a TTC_Server2, TTC_ServerN. | Specify the failover port number where the Server should listen. |
The TTC_ConnectTimeout
attribute specifies the maximum number of seconds the client waits for a SQLDriverConnect
or SQLDisconnect
request. It overrides the value of TTC_Timeout
for those requests. Set the TTC_ConnectTimeout
when you want connection requests to timeout with a different timeframe than the timeout provided for query requests. For example, you can set a longer timeout for connections if you know that it takes a longer time to connect, but set a shorter timeout for all other queries.
A value of 0 means there is no timeout. A negative value defers to the TTC_Timeout
setting. As with TTC_Timeout
, if the timeout is reached, the connection and the associated socket are closed without a call to SQLDisconnect
.
TTC_ConnectTimeout
can be set in either the client connection string or the client DSN.
For more details, see "Choose SQL and PL/SQL timeout values" in the Oracle TimesTen In-Memory Database Operations Guide.
Also see "TTC_Timeout".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_ConnectTimeout
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_ConnectTimeout |
Seconds to wait for a client connect or disconnect request. Default is 20 seconds. |
Windows ODBC Data Source Administrator | Not applicable |
Specifies a port range for the port that the automatic client failover thread listens on for failover notifications in an active/standby replication configuration. The failover configuration enables a client application to connect to a new active node automatically if there is a failure on the current node.
Specifying a port range helps accommodate firewalls between the client and server systems. By default, TimesTen uses a port chosen by the operating system.
See "Using automatic client failover" in Oracle TimesTen In-Memory Database Operations Guide for more information on automatic client failover.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_FailoverPortRange
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_FailoverPortRange |
Specify a lower value and an upper value for the port numbers in the format lowervalue — uppervalue . |
Windows ODBC Data Source Administrator | Failover Port Range field on the Oracle TimesTen Client DSN Setup dialog. | Specify a lower value and an upper value for the port numbers in the format lowervalue — uppervalue . |
Specifies whether the TimesTen client should not automatically reconnect to the server after a failover. If this is set to 1 (enabled), TimesTen is instructed to do all the usual client failover processing except for the reconnect. (For example, statement and connection handles are marked as invalid.) This is useful if the application does its own connection pooling or manages its own reconnection to the database after failover. The default value is 0 (reconnect).
You must configure automatic client failover for this option. See "Client connection failover in the Oracle TimesTen In-Memory Database Scaleout User's Guide for more information.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_NoReconnectOnFailover
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_NoReconnectOnFailover |
0 = Client reconnects to server after failover (default).
|
Windows ODBC Data Source Administrator | No reconnect on failover field on the Oracle TimesTen Client DSN Setup dialog. | 0 = Client reconnects to server after failover (default).
|
Specifies that the TimesTen client, if necessary, selects an alternative server from the list provided in TTC_ServerN
attribute settings. If the client cannot connect to the selected server, it keeps redirecting until it successfully connects to one of the listed servers. If the client cannot connect to any of the selected servers, TimesTen returns an error.
1
(default): Initially, the list of failover servers provided by TTC_ServerN
connection attributes is randomized. After which, the client selects sequentially from the randomized list for the initial connection and then for any client failover request.
0
: Client selects the first server specified by the TTC_ServerN
connection attributes.
See "Using automatic client failover" in Oracle TimesTen In-Memory Database Operations Guide for more information on automatic client failover.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_Random_Selection
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Random_Selection |
0 = Client selects the first server specified by the TTC_ServerN attributes.
|
Windows ODBC Data Source Administrator | Not applicable |
For TimesTen Scaleout, TTC_REDIRECT
defines how a client is redirected. If this is set to 0 and the initial connection attempt to the desired data instance fails, then an error is returned and there are no further connection attempts. This does not affect subsequent failovers on that connection.
Automatic redirection: By default, this connection attribute is set to 1 so that a client connection is automatically redirected to any available data instance within the grid if the current host is busy or unavailable. The connection is redirected to the host with the fewest number of client connections.
Elements within a single replica set: If you want the client to connect to elements within a single replica set (because the data you are interested in is contained within this replica set), then set the TTC_REDIRECT
connection attribute to 0. Then, the client connects only to the host indicated by the DSN or to the host with the element in the same replica set. If the connection is rejected, then a connection error is returned.
The TTC_Redirect_Limit
attribute limits how many times the client is redirected. The number of hosts in your grid can be of a size that you want to limit the number of redirected client connection attempts for performance reasons. You can set the TTC_Redirect_Limit
connection attribute to the number of connection redirection attempts. For example, setting TTC_Redirect_Limit=10
limits the number of client connection redirection attempts to other hosts to 10 attempts. If the client does not connect within this number of attempts, a connection error is returned.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_REDIRECT
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_REDIRECT |
1 (default) - redirect to any available data instance
0 - error if redirection to specified data instance fails |
Windows ODBC Data Source Administrator | Not applicable |
For TimesTen Scaleout, TTC_Redirect_Limit
limits how many times the client is redirected.
This is useful if the number of hosts in your grid is such that you want to limit the number of redirected client connection attempts for performance reasons.
For example, setting TTC_Redirect_Limit=10
limits the number of client connection redirection attempts to other hosts to 10 attempts. If the client does not connect within this number of attempts, a connection error is returned.
Note:
There is no setting for no limit, but you can set it to a very large integer.Usage in TimesTen Scaleout and TimesTen Classic
This attribute is not supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_Redirect_Limit
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Redirect_Limit |
Integer to limit how many times the client is redirected. The default is 1. |
Windows ODBC Data Source Administrator | Not applicable | . |
For TimesTen Classic, indicates if the application must roll back if a client failover occurs. The default setting of 1 (enabled) results in a "transaction must roll back" error on the connection handle and all associated statement handles if failover occurs in the middle of a transaction. This explicitly indicates that the SQL operation may have failed. The application must roll back the transaction before proceeding.
The setting of 0 does not indicate any failures, which could also result in silent data loss. Only use the setting of 0
if necessary for backward compatibility.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_RollbackRequiredOnFailover
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_RollbackRequiredOnFailover |
1 (default) - rollback required
0 - no rollback required |
Windows ODBC Data Source Administrator | Rollback required on failover field on the Oracle TimesTen Client DSN Setup dialog. | 1 (default) - rollback required
0 - no rollback required |
When connecting to a TimesTen database using the TimesTen Client and Server, the TimesTen Client requires the specification of the network address and TCP port number of the computer running the TimesTen Server. The network address provided can be a domain name server (DNS), host name or IP address.
Note:
If you are configuring for client failover, you may define more than one TimesTen Server. See "TTC_Server2, TTC_ServerN" for more information.If the TimesTen Server is listening on a non-default port number, you must provide the port number in one of the following ways:
You can specify the port number within the TTC_Server
connection attribute using:
TTC_SERVER=server_host_name/server_port;
You can specify the port number in the ODBC connection string.
"TTC_SERVER=server_host_name;TTC_SERVER_DSN=Server_DSN; TCP_PORT=server_port"
Or:
"DSN=Client_DSN;TCP_Port=server_port"
If using TimesTen Classic, you can specify the port number within the logical server definition in the ttconnect.ini
file.
See "TCP_Port" for more details.
Note that:
TimesTen Scaleout: You can use either TTC_Server
or TTC_Server1
for TimesTen Scaleout. If you define the TTC_Server
connection attribute, the value is used only for the initial connection.
TimesTen Classic: You can specify a logical server name for the TTC_Server
attribute with TimesTen Classic that contains the network address and port number pair in the ttconnect.ini
file. Once the logical server name is defined in the ttconnect.ini
file, you can use that name as the value for the TTC_Server
attribute in a Client DSN definition. Multiple Client DSNs referencing the same computer that is running the TimesTen Server can use the same logical server name for the value of the TTC_Server
attribute instead of having to specify repeatedly the same network address and port number within each of the Client DSNs. See "Creating and configuring a logical server name on Linux and UNIX" in the Oracle TimesTen In-Memory Database Operations Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_Server
or TTC_Server1
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Server , TTC_Server1 |
Character string specifying the logical server. |
Windows ODBC Data Source Administrator | Server Name or Network Address field on the Oracle TimesTen Client DSN Setup dialog. | Character string specifying the logical server. |
For TimesTen Classic, this attribute specifies the logical server name to use if an automatic failover occurs. See the description of TTC_Server or TTC_Server1
for details on setting the value of this attribute and associated attributes.
When using automatic client failover with an active standby pair replication scheme in TimesTen Classic, you can only define TTC_Server2
. After which, the client alternately attempts to connect to TTC_Server
and TTC_Server2
until a connection succeeds or the TTC_TIMEOUT
attribute expires.
For other types of automatic client failover, you can specify a list of failover servers with TTC_Server
N
connection attributes where N
>= 2
. TimesTen can iterate through this list of designated failover servers (as necessary) that you configured as TTC_Server2
, TTC_Server3
, TTC_Server4
, and so on. The maximum number of servers that the client can specify is 999.
Note:
See "TTC_Random_Selection" on how TimesTen iterates through the list of designated failover servers.Unspecified values for TTC_Server
N
, TTC_Server_DSN
N
, and TCP_Port
N
inherit the value of TTC_Server
(or equivalently, TTC_Server1
), TTC_Server_DSN
(or TTC_Server_DSN1
), and TCP_PORT
(or TCP_PORT1
), respectively. For example, if TTC_Server2
is specified but TTC_Server_DSN2
and TCP_Port2
are not, then TTC_Server_DSN2
is set to the TTC_Server_DSN
value and TCP_Port2
is set to the TCP_Port
value.
You should configure your failover servers sequentially. If you do skip a number when configuring your failover servers, then TimesTen automatically creates the missing definition and assigns it to the server identified by TTC_Server
. In this case, your client could fail over to the same server multiple times.
When using an active standby pair replication scheme for client failover, the TTC_Server or TTC_Server1 and TTC_Server2
connection attributes could potentially have the same setting if it is a virtual IP address. Virtual IP addresses can dynamically move to different hosts; thus, both connection attributes may have the same definition, but could be referencing distinct databases.
See "Using automatic client failover" in Oracle TimesTen In-Memory Database Operations Guide for more information on automatic client failover.
Usage in TimesTen Scaleout and TimesTen Classic
These attributes are supported in TimesTen Classic.
These attributes are supported in TimesTen Scaleout.
Set TTC_Server2
or TTC_ServerN
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Server2 , TTC_ServerN |
Character string specifying the logical server to be used if an automatic failover occurs. |
Windows ODBC Data Source Administrator | Failover Server Name or Network Address field on the Oracle TimesTen Client DSN Setup dialog configures the TTC_Server2 connection attribute. |
Character string specifying the logical server to be used if an automatic failover occurs. |
The TTC_Server_DSN
attribute specifies a Server DSN on the computer running the TimesTen Server.
More details on this topic can be found in "Creating Client DSNs on a TimesTen Client system" in the Oracle TimesTen In-Memory Database Operations Guide.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_Server_DSN
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Server_DSN |
Character string specifying the DSN that resides on the Server. |
Windows ODBC Data Source Administrator | Server DSN field on the Oracle TimesTen Client DSN Setup dialog. | Character string specifying the DSN that resides on the Server. |
For TimesTen Classic, this attribute specifies the Server DSN on the computer running the TimesTen Server. (This is unnecessary for TimesTen Scaleout.) This is the Server DSN to be used if an automatic failover occurs. See the description of TTC_Server_DSN
for details on setting the value of this attribute and associated attributes.
If a failover occurs, if the client cannot connect to TTC_Server_DSN
or loses the connection to the DSN, it attempts to connect to TTC_Server_DSN2
or TTC_Server_DSN
n
.
Unspecified values for TTC_Server_DSN
n
inherit the value of TTC_Server_DSN
(or TTC_Server_DSN1
). For example, if TTC_Server2
is specified but TTC_Server_DSN2
and TCP_Port2
are not, then TTC_Server_DSN2
is set to the TTC_Server_DSN
value and TCP_Port2
is set to the TCP_Port
value.
See "Using automatic client failover" in Oracle TimesTen In-Memory Database Operations Guide for more information on automatic client failover.
Usage in TimesTen Scaleout and TimesTen Classic
These attributes are supported in TimesTen Classic.
These attributes are supported in TimesTen Scaleout.
Set TTC_Server_DSN2
or TTC_Server_DSN
n
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems ODBC .INI file |
TTC_Server_DSN2 , TTC_Server_DSN n |
Character string specifying the DSN that resides on the Server to be used if an automatic failover occurs. |
Windows ODBC Data Source Administrator | Failover Server DSN field (only for TTC_Server_DSN2 ) on the Oracle TimesTen Client DSN Setup dialog. |
Character string specifying the DSN that resides on the Server to be used if an automatic failover occurs. |
The TTC_TCP_KEEPALIVE_INTVL_MS
attribute sets the time interval (in milliseconds) between subsequential probes.
By default, if the connection fails, TimesTen Scaleout sends the client connection to another active server. Part of the method to see if the connection is up or if it has failed is to check the TCP socket. When a TCP connection is started, a set of timers are associated with the connection. These timers indicate when TimesTen Scaleout checks the TCP socket to determine whether the connection is up or if it has failed.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_TCP_KEEPALIVE_INTVL_MS
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_TCP_KEEPALIVE_INTVL_MS |
A positive integer value. Default is 1000 . |
Windows ODBC Data Source Administrator | TCP KeepAlive Interval field on the Oracle TimesTen Client DSN Setup dialog. | A positive integer value. Default is 1000 . |
The TTC_TCP_KEEPALIVE_PROBES
attribute sets the number of unacknowledged probes to send before considering the connection as failed and notifying the client.
By default, if the connection fails, TimesTen Scaleout sends the client connection to another active server. Part of the method to see if the connection is up or if it has failed is to check the TCP socket. When a TCP connection is started, a set of timers are associated with the connection. These timers indicate when TimesTen Scaleout checks the TCP socket to determine whether the connection is up or if it has failed.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_TCP_KEEPALIVE_PROBES
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_TCP_KEEPALIVE_PROBES |
A positive integer value. Default is 2 . |
Windows ODBC Data Source Administrator | TCP KeepAlive Probes field on the Oracle TimesTen Client DSN Setup dialog. | A positive integer value. Default is 2 . |
The TTC_TCP_KEEPALIVE_TIME_MS
attribute sets the duration time (in milliseconds) between the last data packet sent and the first probe.
By default, if the connection fails, TimesTen Scaleout sends the client connection to another active server. Part of the method to see if the connection is up or if it has failed is to check the TCP socket. When a TCP connection is started, a set of timers are associated with the connection. These timers indicate when TimesTen Scaleout checks the TCP socket to determine whether the connection is up or if it has failed.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_TCP_KEEPALIVE_TIME_MS
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_TCP_KEEPALIVE_TIME_MS |
A positive integer value. Default is 1000 . |
Windows ODBC Data Source Administrator | TCP KeepAlive Time field on the Oracle TimesTen Client DSN Setup dialog. | A positive integer value. Default is 1000 . |
The TTC_Timeout
attribute sets a maximum time limit, in seconds, for a network operation that is completed by using the TimesTen Client and Server. The TTC_Timeout
attribute also determines the maximum number of seconds a TimesTen Client application waits for the result from the corresponding TimesTen Server process before timing out. For example, if the Client application is running long queries, you may want to increase the timeout interval.
The operating systemselect()
call on the client side of a client/server connection uses the value of TTC_Timeout
. The SQLExecute()
and OCIStmtExecute()
functions do not.
A value of 0 indicates that client/server operations should not timeout. If this attribute is not set, the default timeout period is 60 seconds. The maximum timeout period is 99,999 seconds. Upon timeout, the operation is interrupted, the Client application receives a timeout error and the connection is terminated and socket closed (without a call to SQLDisconnect
).
For active standby pair failover scenarios, the minimum value is 60 seconds.
The timeout value can be set after establishing a connection by calling the ttIsql clienttimeout
command. When the query timeout is set after establishing a connection to the database, the client driver returns an error if the network timeout value is greater than 0, and the query timeout value greater than or equal to the network timeout value. The SQLState
is set to S1000.
This attribute is not supported (the setting ignored) when shared memory is used for Client/Server inter-process communication.
See "Choose SQL and PL/SQL timeout values" in Oracle TimesTen In-Memory Database Operations Guide for information about the relationship between TTC_Timeout
, SQLQueryTimeout
, and PLSQL_TIMEOUT
.
TTC_Timeout
can be overridden for connect and disconnect requests by TTC_ConnectTimeout
. See "TTC_ConnectTimeout".
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set TTC_Timeout
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
TTC_Timeout |
A value between 0 and 99999 that represents the number of seconds that the TimesTen Client waits for an operation to complete before timing out. (The default value is 60 .) In an active standby pair failover scenario, the minimum value is 60. |
Windows ODBC Data Source Administrator | Network Timeout field on the Oracle TimesTen Client DSN Setup dialog. | A value between 0 and 99999 that represents the number of seconds that the TimesTen Client waits for an operation to complete before timing out. (The default value is 60 .) In an active standby pair failover scenario, the minimum value is 60. |
The Wallet
attribute specifies the fully qualified directory path name, where you placed the certificates that you generated (preferably the same directory path as on the client). There is no default location. If you specify a relative path, it is relative to the timesten_home
/info
directory.
You must set this attribute for both the client and the server. You must set the same path on both the client and server.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Wallet
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Wallet |
A fully qualified directory path name (no default). |
Windows ODBC Data Source Administrator | Wallet field on the Oracle TimesTen Client DSN Setup dialog. | A fully qualified directory path name (no default). |
Server connection attributes are specified in the Server DSN only and are read at first connection. See "Defining Server DSNs for TimesTen Server on a Linux or UNIX system" in Oracle TimesTen In-Memory Database Operations Guide. Use these attributes to set the number of connections to a TimesTen server, the number of servers for each DSN and the size of each connection to the server. These attributes allow you to specify multiple client connections to a single Server. By default, TimesTen creates only one connection to a Server per child process.
Note:
These attributes must be specified in the DSN. If these attributes are specified in a connection string, TimesTen ignores them and their values.There are also TimesTen main daemon options that can specify multiple Server connections. In the case that both the daemon options and these attributes have been specified, the value of the attributes takes precedence.
Server connection attributes are listed in Table 2-11, "TimesTen Server connection attributes" and described in detail in this section.
The CipherSuites
attribute lists the cipher suite or suites that can be used, depending also on the client setting. Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
, SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
, or both, comma-separated and in order of preference. There is no default setting.
You must set this attribute for both the client and the server. For TLS to be used, the server and client settings must include at least one common suite.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set CipherSuites
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
CipherSuites | Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 , SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 , or both, comma-separated and in order of preference |
Windows ODBC Data Source Administrator | Encryption field on the Oracle TimesTen Client DSN Setup dialog. | Specify SSL_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 , SSL_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 , or both, comma-separated and in order of preference |
The Encryption
attribute specifies whether encryption is required or not for a client server connection.
You must set this attribute for both the client and the server. Cipher settings must be the same on both the client and server, in most cases.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set Encryption
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
Encryption |
|
Windows ODBC Data Source Administrator | Encryption field on the Oracle TimesTen Client DSN Setup dialog. |
|
The SSLClientAuthentication
attribute specifies whether SSL client authentication is required (setting of 1) or not (setting of 0, the default). With client authentication, the server validates an identity presented by the client, and requires an identity (public/private key) in the client wallet.
Regardless of the client authentication setting, server authentication is performed, where the client validates the server.
You must set this attribute for both the client and the server. Regardless of the client authentication setting, server authentication is performed, where the client validates the server.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set SSLClientAuthentication
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
SSLClientAuthentication |
1 - Client authentication is required
|
Windows ODBC Data Source Administrator | SSL Client Authentication field on the Oracle TimesTen Client DSN Setup dialog. | 1 - Client authentication is required
|
The MaxConnsPerServer
attribute sets the maximum number of concurrent connections to the server which the DSN references.
If you want to support many connections to the Server, you must ensure that the per-process file descriptor limit for the UID
that TimesTen is being run as is set to a value somewhat more than the number of concurrent child servers that are active. This is the number of anticipated concurrent client connections divided by MaxConnsPerServer
. For full details on MaxConnsPerServer
, see "Connection attributes for Data Manager DSNs or Server DSNs" in the Oracle TimesTen In-Memory Database Operations Guide.
The value of this attribute takes precedence over the setting of the value of the max_conns_per_server
attribute in the timesten.conf
file. For details, see "Specifying multiple connections to the TimesTen Server" in Oracle TimesTen In-Memory Database Operations Guide.
For limits on the maximum number of connections to a TimesTen database, see Chapter 6, "System Limits".
Changes to TimesTen Server settings do not occur until the TimesTen server is restarted. To restart the Server, use the command ttDaemonAdmin -restartserver
.
Only a user with operating system privileges on the system DSN in which this attribute is defined can change the value of this attribute to a value other than the one currently in effect.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set MaxConnsPerServer
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
MaxConnsPerServer |
A value between 1 and 2047. The default is 1 , which indicates that each connection has its own separate process, not just a separate thread within a process. |
Windows ODBC Data Source Administrator | Not applicable |
The ServersPerDSN
attribute specifies the number of child server processes for a particular server DSN that will use round-robin connection distribution.
This attribute only has any effect if the TimesTen server is configured to operate in multithreaded mode (MaxConnsPerServer > 1
). If ServersPerDSN
is set to 1 then the first MaxConnsPerServer
client connections to the server DSN will be assigned to one child server process, the next MaxConnsPerServer
connections to a second child server process and so on. See "Connection attributes for Data Manager DSNs or Server DSNs" in the Oracle TimesTen In-Memory Database Operations Guide for more details.
The value of this attribute takes precedence over the setting of the value of the servers_per_dsn
attribute in the timesten.conf
file. For details, see "Specifying multiple connections to the TimesTen Server" in the Oracle TimesTen In-Memory Database Operations Guide.
Changes to TimesTen Server settings do not occur until the TimesTen server is restarted. To restart the Server, use the command ttDaemonAdmin -restartserver
.
Only a user with operating system privileges on the system DSN in which this attribute is defined can change the value of this attribute to a value other than the one currently in effect.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set ServersPerDSN
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
ServersPerDSN |
A value between 1 and 2047. The default is 1 . |
Windows ODBC Data Source Administrator | Not applicable |
The ServerStackSize
attribute value determines the size of the stack on the Server for each connection. The value of this attribute is only meaningful if the value of MaxConnsPerServer
is greater than one. If there is only one connection per Server, the child server uses the process' main stack. It is also platform-dependent, as defined in the setting below.
You generally should not need to set the ServerStackSize
attribute. However, if the ttcserver
process is getting repeatable Access Violations (Windows) or core dumps (Linux and Unix), you may consider increasing the ServerStackSize
attribute to 1024 KB or greater.
This value of this attribute takes precedence over the setting of the server_stack_size
attribute in the timesten.conf
file. For details, see "Specifying multiple connections to the TimesTen Server" in Oracle TimesTen In-Memory Database Operations Guide.
Changes to TimesTen Server settings do not occur until the TimesTen server is restarted. To restart the Server, use the command ttDaemonAdmin -restartserver
.
Only a user with operating system privileges on the system DSN in which this attribute is defined can change the value of this attribute to a value other than the one currently in effect.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set ServerStackSize
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
ServerStackSize |
Valid values depend on the platform. The default is 768 KB.
If the
else the minimum is 0. |
Windows ODBC Data Source Administrator | Not applicable |
The SSLRenegotiationPeriod
attribute specifies a period of time, in minutes, after which session renegotiation is performed. The default setting is 0, meaning do not renegotiate based on a time period.
Changes to TimesTen Server settings do not occur until the TimesTen server is restarted. To restart the Server, use the command ttDaemonAdmin -restartserver
.
If both SSLRenegotiationSize
and SSLRenegotiationPeriod
are set with non-zero values, whichever setting occurs first causes the renegotiation.
For more details see "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide.
Only a user with operating system privileges on the system DSN in which this attribute is defined can change the value of this attribute to a value other than the one currently in effect.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set SSLRenegotiationPeriod
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
SSLRenegotiationPeriod |
An integer representing the number of minutes to wait to for session renegotiation.
|
Windows ODBC Data Source Administrator | Not applicable |
The SSLRenegotiationSize
attribute specifies a number of megabytes of data transfer in either direction between the client and server, after which session renegotiation is performed. The default setting is 0, meaning do not renegotiate based on megabytes transferred.
Changes to TimesTen Server settings do not occur until the TimesTen server is restarted. To restart the Server, use the command ttDaemonAdmin -restartserver
.
If both SSLRenegotiationSize
and SSLRenegotiationPeriod
are set with non-zero values, whichever setting occurs first causes the renegotiation.
For more details see "Configuration for TLS for Client Server" in the Oracle TimesTen In-Memory Database Security Guide.
Only a user with operating system privileges on the system DSN in which this attribute is defined can change the value of this attribute to a value other than the one currently in effect.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is not supported in TimesTen Scaleout.
Set SSLRenegotiationSize
as follows:
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic |
SSLRenegotiationSize |
An integer representing the number of megabytes of data transfer after which the session restart is renegotiated.
|
Windows ODBC Data Source Administrator | Not applicable |
The Wallet
attribute specifies the fully qualified directory path name, where you placed the certificates that you generated (preferably the same directory path as on the client). There is no default location. If you specify a relative path, it is relative to the timesten_home
/info
directory.
You must set this attribute for both the client and the server. You must set the same path on both the client and server.
See "Configuration for TLS for Client/Server" in the Oracle TimesTen In-Memory Database Security Guide for more details.
Usage in TimesTen Scaleout and TimesTen Classic
This attribute is supported in TimesTen Classic.
This attribute is supported in TimesTen Scaleout.
Set Wallet
as follows.
Where to set the attribute | How the attribute is represented | Setting |
---|---|---|
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef ) file in TimesTen Scaleout |
Wallet |
A fully qualified directory path name (no default). |
Windows ODBC Data Source Administrator | Wallet field on the Oracle TimesTen Client DSN Setup dialog. | A fully qualified directory path name (no default). |