The Oracle database server initialization parameters in the init.ora file are distinct from heterogeneous services (HS) initialization parameters. Set HS parameters in the initialization parameter file using an agent-specific mechanism, or set them in the Oracle data dictionary using the DBMS_HS package.
This appendix contains information about the following Heterogeneous Services initialization parameters:
See Also: Oracle Database Heterogeneous Connectivity Administrator's Guide for information on other available initialization parameters. |
The HS initialization parameter file must be available when the gateway is started. During installation, the following default HS initialization parameter file is created:
$ORACLE_HOME/tg4tera/admin/inittg4tera.ora
Where $ORACLE_HOME is the directory under which the gateway is installed.
The syntax for the initialization parameter file is as follows:
The file is a sequence of commands.
Each command should start on a separate line.
End of line is considered a command terminator (unless escaped with a backslash).
Each command can have one of the following forms:
<param> = <value>
set <param> = <value>
private <param> = <value>
set private <param> = <value>
Where:
<param>
is an initialization parameter name.
<value>
is the initialization parameter value.
'set
' and 'private
' are keywords.
The keywords 'set
' and 'private
' are reserved. You cannot use either as an initialization parameter name. The 'set
' keyword indicates that the initialization parameter should be set as an environment variable in the agent. The 'private
' keyword indicates that the initialization parameter should be private to the agent and should not be uploaded to the server. Most initialization parameters should not be private. If, however, you are storing something sensitive like a password in the initialization parameter file, then you may not want it uploaded to the server because the initialization parameters and values are not encrypted when uploaded. Making these initialization parameters private prevents the upload from happening.
An initialization parameter name is a string of characters starting with a letter and consisting of letters, digits and underscores. Initialization parameter names are case sensitive.
An initialization parameter value is either:
A string of characters that does not contain any backslashes, white space or double quotation marks (").
A quoted string beginning with a double quotation mark and ending with a double quotation mark. The following can be used inside a quoted string:
backslash (\) is the escape character
\n inserts a new line
\t inserts a tab
\" inserts a double quotation mark
\\ inserts a backslash
A backslash at the end of the line continues the string on the next line. If a backslash precedes any other character then the backslash is ignored.
If there is a syntax error in an initialization parameter file, none of the settings take effect.
Default Value | Range of Values |
---|---|
None | Not Applicable |
Specifies the information needed to connect to the Teradata database.
This is a required parameter, whose format is:
HS_FDS_CONNECT_INFO=dsn
Where:
dsn is the Data Source Name defined in the odbc.ini
file.
Default Value | Range of Values |
---|---|
1,000 Characters | Any positive integer value |
Used for setting the parser token size in case the default size is not sufficient. The default value can be changed in cases when the following error occurs:
pclex input buffer overflowed, try to increase the variable tokenSize in your evironment.
With default value of 1000, the gateway could handle SQL statements close to 2M. Note that the SQL statements sent to the gateway could be very different from the SQL statements issued by the users. If in doubt, turn on gateway trace. Increase this parameter to handle larger SQL statements sent to gateways.
Default Value | Range of Values |
---|---|
RECOVER | Any valid userid |
Specifies the name of the recovery account used for the commit-confirm transaction model. An account with user name and password must be set up at Teradata. For more information about the commit-confirm model, see the HS_FDS_TRANSACTION_MODEL parameter.
The name of the recovery account is case-sensitive.
Default Value | Range of Values |
---|---|
RECOVER | Any valid password |
Specifies the password of the recovery account used for the commit-confirm transaction model set up at Teradata. For more information about the commit-confirm model, see the HS_FDS_TRANSACTION_MODEL parameter.
The name of the password of the recovery account is case-sensitive.
Default Value | Range of Values |
---|---|
None | Not applicable |
Specifies the full path name to the ODBC library.
This is a required parameter, whose format is:
HS_FDS_SHAREABLE_NAME=odbc_installation_path/lib/libodbc.sl
Where:
odbc_installation_path is the path where the NCR Teradata ODBC Driver is installed.
Default Value | Range of Values |
---|---|
OFF | OFF, ON |
Specifies whether error tracing is turned on or off for gateway connectivity.
The following values are valid:
OFF disables the tracing of error messages.
ON enables the tracing of error messages that occur when you encounter problems. The results are written to a gateway connectivity log file, in $ORACLE_HOME/TG4TERA/LOG
.
Default Value | Range of Values |
---|---|
HS_TRANSACTION_LOG | Any valid table name |
Specifies the name of the table created in the Teradata database for logging transactions. For more information about the transaction model, see the HS_FDS_TRANSACTION_MODEL parameter.
Default Value | Range of Values |
---|---|
COMMIT_CONFIRM | COMMIT_CONFIRM, READ_ONLY, or SINGLE_SITE |
Specifies the type of transaction model that is used when the Teradata database is updated by a transaction.
The following values are possible:
COMMIT_CONFIRM provides read and write access to the Teradata database and allows the gateway to be part of a distributed update. To use the commit-confirm model, the following items must be created in the Teradata database:
Transaction log table. The default table name is HS_TRANSACTION_LOG. A different name can be set using the HS_FDS_TRANSACTION_LOG parameter. The transaction log table must be granted SELECT, DELETE, and INSERT privileges set to public.
Recovery account. The account name is assigned with the HS_FDS_RECOVERY_ACCOUNT parameter.
Recovery account password. The password is assigned with the HS_FDS_RECOVERY_PWD parameter.
READ_ONLY provides read access to the Teradata database.
SINGLE_SITE provides read and write access to the Teradata database. However, the gateway cannot participate in distributed updates.