5 Tuning and Troubleshooting

This chapter provides information about tuning, troubleshooting, and error handing in Oracle Objects for OLE (OO4O).

This chapter contains these topics:

Tips and Techniques for Performance Tuning

The following topics are intended to help tune the performance of applications that use Oracle Objects for OLE.

This section contains these topics:

Early Binding of OO4O Objects

The early binding technique tightly typecasts OO4O objects to their native object types rather than the generic object type provided by Visual Basic. These objects are declared directly as OO4O objects, rather than as generic objects which are later reclassified as OO4O objects. Early binding improves performance by reducing frequent access to the OO4O type library. For example:

'Early binding of OO4O objects 
Dim OraSession as OraSession 
Dim OraDatabase as OraDatabase 
Dim OraDynaset as OraDynaset 
 
'Generic binding of OO4O objects 
 
Dim OraSession as Object 
Dim OraDatabase as Object 
Dim OraDynaset as Object 

To use early binding of OO4O objects, the Oracle In-Process Server type library must be referenced in the Visual Basic projects.

Tuning and Customization

Data access can be tuned and customized by altering the cache and fetch parameters of a dynaset. Setting the FetchLimit parameter to a higher value increases the number of rows that are fetched with each request, thus reducing the number of network trips to Oracle Database, and improving performance.

The cost of increasing the size of the FetchLimit parameter is that it increases memory requirements on the client side, and causes more data to be swapped to and from the temporary cache file on disk. The proper FetchLimit value should be set according to the client computer configuration and the anticipated size of the query result.

The FetchLimit value can be set in the following ways:

  • By using the CreateCustomDynaset method

  • By modifying parameters of the OO4O entry in the Windows registry

For Windows, the registry key is HKEY_LOCAL_MACHINE and the subkey is software\oracle\KEY_HOMENAME\oo4o, where HOMENAME is the appropriate Oracle home. The OO4O installation creates the following section in the registry:

"FetchLimit" = 100

Avoiding Multiple Object Reference

Improper coding techniques with unnecessary object references can also affect performance. During dynaset object navigation, you should reduce the number of object references to the OraFields collections and OraField objects. The following is an inefficient code block:

'Create the OraDynaset Object 
Set OraDynaset = OraDatabase.CreateDynaset("select * from emp", 0&) 
 
'Traverse until EOF is reached 
Do Until OraDynaset.EOF 
    msgbox OraDynaset.Fields("sal").value 
OraDynaset.MoveNext 
Loop 

The OraDynaset, OraFields collections, and OraField objects are referenced for each iteration. Although OO4O provides improvement in handling the field collections object, multiple references to the automation object goes though the underlying OLE/COM automation layer, which slows down the execution.

The following example shows how to reference fields through a field object and not through the fields collection of the dynaset. Testing has determined that this small amount of extra code greatly improves performance.

Dim flds() As OraField 
Dim i, fldcount As Integer 
 
' Create the OraDynaset Object 
Set OraDynaset = OraDatabase.CreateDynaset("select * from emp", 0&) 
' Get the field count, and output the names 
fldcount = OraDynaset.Fields.Count 
ReDim flds(0 To fldcount - 1) 
 
For i = 0 To fldcount - 1 
Set flds(i) = OraDynaset.Fields(i) 
Next I 
'Traverse until EOF is reached 
 
Do Until OraDynaset.EOF 
   msgbox Flds(5).Value 
   msgbox Flds(6).Value 
OraDynaset.MoveNext 
Loop 

Any method or object that is referenced through more than one object is potentially inefficient, but the extra coding to avoid this is not always worth the time saved. The best place to start is with field references, because they are most likely to occur multiple times.

Parameter Bindings

OO4O provides a way of enabling and disabling parameter object binding at the time it processes the SQL statement. This can be done through the AutoBindDisable and AutoBindEnable methods of the OraParameter object. If the SQL statement does not contain the parameter name, it is better to disable the OraParameter object because it avoids an unnecessary reference to the parameter object. This is most effective when the application is written primarily using PL/SQL procedures. For example:

Set OraDatabase = OraSession. OpenDatabase("Exampledb", "scott/tiger", 0&) 
 
'Add the job input parameter with initial value MANAGER. 
OraDatabase.Parameters.Add "job", "MANAGER", 1 
 
'Add the deptno input parameter with initial value 10. 
OraDatabase.Parameters.Add "deptno", 10, 1 
 
'Add the job input parameter with initial value MANAGER. 
OraDatabase.Parameters.Add "EmpCur", 0, 1 
OraDatabase.Parameters("Empcur").ServerType = ORATYPE_CURSOR 
 
'Disable the job parameter for now. 
OraDatabase.Parameters("job").AutoBindDisable 
 
set OraSqlStmt = CreateSQL("Begin GetEmpData(:Empcur, :deptno) End;",0&) 

Note how the job parameter object is not referenced while processing the PL/SQL statement.

Array Processing

OO4O supports an array interface to an Oracle database through the OraParamArray object. The array interface enables the transfer of bulk of data in single network trip. This is especially helpful while processing a PL/SQL or SQL statement through the ExecuteSQL or CreateSQL method. For example, in order to insert 100 rows into remote database without array processing, ExecuteSQL or CreateSQL must be called 100 times, which in turn makes 100 network trips. For example:

For I = 1 to 100 
   OraParameter("EMPNO").Value = xxxx 
   OraParameter("ENAME").Value = 'yyyy' 
   OraParameter("DEPTNO").Value = zz 
   OraDatabase.ExecuteSql("insert into emp values (:EMPNO,:ENAME,:DEPTNO)"); 
Next I 

The following example makes use of arrays and makes only one network trip.

'ENAMEARR,:EMPNOARR,:DEPTNOARR are parameter arrays 
 
For I = 1 to 100 
   OraParameter("EMPNOARR").Put_Value xxxx, I 
   OraParameter("ENAMEARR").Put_Value 'yyyy' ,I 
   OraParameter("DEPTNOARR").Put_Value zz, I 
Next I 
 
'Now call the ExecuteSQL only once 
OraDatabase.ExecuteSql("insert into emp values(:EMPNOARR," & _
              ":ENAMEARR, :DEPTNOARR)"); 

See Also:

OraParamArray Object for more information on using arrays

Using Read-Only, Forward-Only Dynaset

If your application does not make any updates to the dynaset, then you can create a read-only dynaset with the ORADYN_READONLY (H4) option. With this option, performance improvement can be gained by eliminating the overhead of parsing SQL statements locally and reducing network trips for SQL statement execution.

If your application does not need a scrollable dynaset, then you can create a forward-only dynaset with the ORADYN_NOCACHE (H8) option. With this option, performance improvement can be gained by eliminating the overhead of creating a local cache file and the overhead of reading/writing data from that file.

Using the PL/SQL Bulk Collection Feature

The PL/SQL bulk collection feature enables the selecting of bulk data in a single network trip using PL/SQL anonymous blocks. The OO4O OraDynaset object selects arrays of data during SQL statement execution. This involves overhead such as performing more network round-trips, creating more cache files and internal objects. If you do not want to use a dynaset due to its overhead, then this feature is useful for selecting arrays of data. The data to be selected can be bound either as an OraParamArray object or as an OraCollection object.

The following example illustrates PL/SQL bulk collection features using the OraCollection interface. It shows how arrays of enames are selected with one network round-trip and less overload.

Set OraDatabase = OraSession.OpenDatabase("Exampledb", "scott/tiger", 0&) 
 
'create a VARRAY type ENAMELIST in the database 
OraDatabase.ExecuteSQL ("create type ENAMELIST as VARRAY(50) OF VARCHAR2(20)")
 
'create a parameter for ENAMELIST VARRAY 
OraDatabase.Parameters.Add "ENAMES", Null, ORAPARM_OUTPUT, 247,"ENAMELIST"  

'execute the statement to select all the enames from ename column of emp table
OraDatabase.ExecuteSQL ("BEGIN select ENAME bulk collect into" & _ 
                ":ENAMES from emp; END;") 
 
'here OraParameter object returns EnameList OraCollection 
Set EnameList = OraDatabase.Parameters("ENAMES").Value 
 
'display all the selected enames 
FOR I = 1 to EnameList.Size 
   msgbox Enamelist(I) 
NEXT I 

Migration from LONG RAW to LOB or BFILE

Oracle8i introduced the following new types described in "Using Large Objects (LOBs)":

  • BLOB

  • CLOB

  • BFILE

The design of these types allows OO4O to access them much faster than using LONG or LONG RAW types. For this reason, convert existing LONG RAW code to BLOB, CLOB, and BFILE, and only use LOBs and BFILEs for new applications. The OraLOB object should be used to access LOB and BFILE types, rather than these LONG RAW chunking methods, which are provided for backward compatibility only. Note that OraLOB offers maximum control.

LOB data types differ from LONG and LONG RAW data types in several ways:

  • A table can contain multiple LOB columns, but can contain only one LONG column.

  • A table containing one or more LOB columns can be partitioned, but a table containing a LONG column cannot be partitioned.

  • The maximum size of a LOB is 4 gigabytes, but the maximum size of a LONG is 2 gigabytes.

  • LOBs support random access to data, but LONGs data types support only sequential access.

  • LOB data types (except NCLOB) can be attributes of a user-defined object type, but LONG data types cannot.

  • LOB client-side buffering is used to optimize multiple small writes.

  • LOB data can be stored in operating system files outside of database tablespaces (BFILE types).

To make migration easier, the following methods can be used with BLOB, CLOB, and BFILE types:

For older applications using the LONG RAW chunking methods, migration should not require a lot of changes to the code. The primary code changes involve the requirement that null BLOB and CLOB types be updated with empty before being used.

Using Connection Pooling

The connection pool in OO4O is a pool of OraDatabase objects. An OO4O connection pool is a group of (possibly) already connected OraDatabase objects. For applications that require constant connections and disconnections to the database, such as ASP Web applications, using a connection pool results in enhanced performance.

Oracle Objects for OLE Error Handling

OO4O errors are grouped in the following categories:

OLE Automation Errors

The programmatic interface of the OO4O automation server is the OO4O In-Process Automation server. Errors that occur during execution of methods are frequently reported as an OLE Automation Error (ERR = 440, ERROR$="OLE Automation Error").

When an error occurs, check the LastServerErr property of the OraSession and OraDatabase objects to determine whether an Oracle database error has occurred. If the LastServerErr is not zero, then an error has been raised by the OO4O automation server.

To find OO4O automation server errors, scan the string returned by the ERROR$ function for the string "OIP-NNNN" where NNNN is an error number included in the Table 5-1.

Note:

These values are included in the oraconst.txt file in the ORACLE_BASE\ORACLE_HOME\oo4o directory.

Table 5-1 lists the Oracle OLE automation errors.

Table 5-1 Oracle OLE Automation Errors

Constant Value Description

OERROR_ADVISEULINK

4096

Internal error: Invalid advisory connection.

OERROR_POSITION

4098

An attempt was made to retrieve a field value from an empty dynaset.

OERROR_NOFIELDNAME

4099

An invalid field name was specified.

OERROR_NOFIELDINDEX

4100

An invalid field index was specified. The range of indexes is 0 to FieldCount-1.

OERROR_TRANSIP

4101

A BeginTrans operation was specified while a transaction was already in progress.

OERROR_TRANSNIPC

4104

A CommitTrans operation was specified without first executing a BeginTrans.

OERROR_TRANSNIPR

4105

A Rollback operation was specified without first executing a BeginTrans.

OERROR_NODSET

4106

Internal error: System attempted to remove a nonexistent dynaset.

OERROR_INVROWNUM

4108

An attempt was made to reference an invalid row. This happens when EOF or BOF is True, or when the current row was deleted and no record movement occurred.

OERROR_TEMPFILE

4109

An error occurred while trying to create a temporary file for data caching.

OERROR_DUPSESSION

4110

An attempt was made to create a named session that already exists, using the CreateSession or CreateNamedSession method.

OERROR_NOSESSION

4111

Internal error: System attempted to remove a nonexistent session.

OERROR_NOOBJECTN

4112

An attempt was made to reference a named object of a collection (other than the fields collection) that does not exist.

OERROR_DUPCONN

4113

Internal error: Duplicate connection name.

OERROR_NOCONN

4114

Internal error: System attempted to remove a nonexistent connection.

OERROR_BFINDEX

4115

An invalid field index was specified. The range of indexes is 0 to Count -1.

OERROR_CURNREADY

4116

Internal error: System attempted to move to a row but the dynaset does not support this operation.

OERROR_NOUPDATES

4117

An attempt was made to change the data of a nonupdatable dynaset.

OERROR_NOTEDITING

4118

An attempt was made to change the value of a field without first executing the Edit method.

OERROR_DATACHANGE

4119

An attempt was made to edit data in the local cache, but the data on Oracle Database was changed.

OERROR_NOBUFMEM

4120

Out of memory for data binding buffers.

OERROR_INVBKMRK

4121

An invalid bookmark was specified.

OERROR_BNDVNOEN

4122

Internal error: Bind variable was not enabled.

OERROR_DUPPARAM

4123

An attempt was made to create a named parameter using the Add method, but that name already exists.

OERROR_INVARGVAL

4124

An invalid offset or length parameter was passed to the GetChunk method, or an internal error occurred using the AppendChunk method.

OERROR_INVFLDTYPE

4125

An attempt was made to use the GetChunk or AppendChunk method on a field that was not either Long or Long Raw type.

OERROR_INVARG

4126

An invalid argument value was entered.

OERROR_TRANSFORUP

4127

A SELECT ... FOR UPDATE operation was specified without first executing the BeginTrans operation.

OERROR_NOTUPFORUP

4128

A SELECT ... FOR UPDATE operation was specified, but the query is nonupdatable.

OERROR_TRANSLOCK

4129

A Commit or Rollback was executed while a SELECT ... FOR UPDATE operation was in progress.

OERROR_CACHEPARM

4130

An invalid cache parameter was specified. Note that the maximum value for the CacheBlocks parameter is 127.

OERROR_FLDRQROWID

4131

An attempt was made to reference a field that requires a ROWID (Long or Long Raw), but the ROWID value was not available.

OERROR_OUTOFMEMORY

4132

Internal Error: Out of memory.

OERROR_MAXSIZE

4135

Element size specified in the AddTable method exceeds the maximum size allowed for that variable type. See "AddTable Method" for more details.

OERROR_INVDIMENSION

4136

Dimension specified in the AddTable method is invalid (that is, negative). See "AddTable Method" for more details.

OERROR_ARRAYSIZ

4138

Dimensions of array parameters used in the INSERT, UPDATE, and DELETE statements are not equal.

OERROR_ARRAYFAILP

4139

Error processing arrays. For details see the oo4oerr.log in the Windows directory.

OE_CLIPFAIL

4141

Internal error: Clipboard could not be opened or closed.

OE_NOSOURCE

4143

No source string was provided for the UpdateResource method.

OE_INVSOURCE

4144

Invalid source type was provided for UpdateSource method.

OE_PLSQLDYN

4145

An attempt was made to set SQL property for dynaset created from PL/SQL cursor.

OERROR_CREATEPOOL

4147

Database pool already exists for this session.

OERROR_GETDB

4148

Unable to obtain a free database object from the pool.

OE_INVINPUTTYP

4149

Input type is not compatible with the field or parameter type.

OE_NOEDITONCLONE

4150

An attempt was made to edit a cloned object.

OE_BNDCHGTYPERR

4152

An attempt was made to change the type of a parameter array or an array of extended type.


Nonblocking Errors

Table 5-2 lists the nonblocking errors.

Table 5-2 Nonblocking Errors

Constant Value Description

OERROR_NONBLKINPROGRESS

4153

Nonblocking operation in progress.

OERROR_NONONBLKINPROGRESS

4154

Operation is valid only when nonblocking operation is in progress.


Find Method Parser Errors

Find method parser errors occur when the parser cannot evaluate the expression in the Find method. These errors specify the part of the expression that caused the error.

Table 5-3 lists the Find method parser errors.

Table 5-3 Find Method Parser Errors

Constant Value Description

OERROR_STACK_OVER

4496

Stack overflow.

OERROR_SYNTAX

4497

Syntax error.

OERROR_MISPLACED_PAREN

4498

Misplaced parenthesis.

OERROR_MISPLACED_QUOTE

4499

Misplaced quotation marks.

OERROR_MISSING PAREN

4500

Warning: Missing closing parenthesis.

OERROR_EXPECTED_PAREN

4501

Open parenthesis expected.

OERROR_PARSER_UNKNOWN

4502

Unknown parser error condition.

OERROR_INVALID_FUNCTION

4503

Syntax not supported.

OERROR_INVALID_COLUMN

4504

Invalid column name.

OERROR_MAX_TOKEN

4505

Maximum size exceeded in token.

OERROR_PARSER_DATA_TYPE

4506

Unsupported data type.

OERROR_UNEXPECTED_TOKEN

4507

Unexpected token found.

OERROR_END_OF_CLAUSE

4508

Unexpected end of clause.


Find Method Run-Time Errors

Find method run-time errors occur when the system cannot evaluate a find expression. Such errors are rare. When one occurs, the parser could have generated incorrect code.

Table 5-4 lists the Find method run-time errors.

Table 5-4 Find Method Run-Time Errors

Constant Value Description

OERROR_INVALID_INSTR

4516

Internal error: Invalid instruction.

OERROR_STACK_ERROR

4517

Internal error: Stack overflow or underflow.

OERROR_CONVERT_TYPES

4518

Invalid type conversion.

OERROR_RUNTIME_DATA_TYPE

4519

Invalid data type.

OERROR_INVALID_SQL_ARG

4520

SQL function missing an argument.

OERROR_INVALID_COMPARE

4521

Invalid comparison.

OERROR_SELECT_DUAL

4522

SELECT from dual failed.

OERROR_DUAL_DATATYPE

4523

Invalid data type in SELECT from dual.

OER_OPER

4524

Invalid use of operator.


OraObject Instance Errors

Table 5-5 lists the OraObject instance errors.

Table 5-5 OraObject Instance Errors

Constant Value Description

OERROR_NOOBJECT

4796

Creating an OraObject object instance in the client-side object cache failed.

OERROR_BINDERR

4797

Binding an OraObject object instance to a SQL statement failed.

OERROR_NOATTRNAME

4798

Getting the attribute name of an OraObject object instance failed.

OERROR_NOATTRINDEX

4799

Getting the attribute index of an OraObject object instance failed.

OERROR_INVINPOBJECT

4801

Invalid input object type for the binding operation.

OERROR_BAD_INDICATOR

4802

Fetched OraObject instance has an invalid indicator structure.

OERROR_OBJINSTNULL

4803

Operation on the NULL OraObject instance failed. See the "IsNull (OraObject) Property".

OERROR_REFNULL

4804

Pin operation on the NULL Ref value failed. See the "IsRefNull (OraRef) Property".


LOB Errors

Table 5-6 lists the LOB errors.

Table 5-6 LOB Errors

Constant Value Description

OERROR_INVSEEKPARAMS

4897

Invalid seek value is specified for the LOB read/write operation.

OERROR_LOBREAD

4898

Read operation failed.

OERROR_LOBWRITE

4899

Write operation failed.

OEL_INVCLOBBUF

4900

Input buffer type for CLOB write operation is not string.

OEL_INVBLOBBUF

4901

Input buffer type for BLOB write operation is not byte.

OERROR_INVLOBLEN

4902

Invalid buffer length for the LOB write operation.

OERROR_NOEDIT

4903

Write, Trim, Append, Copy operations are not allowed in this mode.

OERROR_INVINPUTLOB

4904

Invalid input LOB for the bind operation.

OERROR_NOEDITONCLONE

4905

Write, Trim, Append, Copy operations are not allowed for a cloned LOB object.

OERROR_LOBFILEOPEN

4906

Specified file could not be opened during a LOB operation.

OERROR_LOBFILEIOERR

4907

File Read or Write operation failed during a LOB operation.

OERROR_LOBNULL

4908

Operation on NULL LOB failed. See "IsNull (OraLOB/BFILE) Property".


Oracle Streams Advanced Queuing Errors

Table 5-7 lists the Oracle Streams Advanced Queuing errors.

Table 5-7 Oracle Streams Advanced Queuing Errors

Constant Value Description

OERROR_AQCREATEERR

4996

Error creating the OraAQ Object.

OERROR_MSGCREATEERR

4997

Error creating the AQMsg object.

OERROR_PAYLOADCREATEERR

4998

Error creating the payload object.

OERROR_MAXAGENTS

4999

Maximum number of subscribers exceeded.

OERROR_AGENTCREATEERR

5000

Error creating the AQAgent object.


See Also:

OraAQ Object

OraCollection Errors

Table 5-8 lists the OraCollection errors.

Table 5-8 OraCollection Errors

Constant Value Description

OERROR_COLLINSTNULL

5196

Operation on NULL OraCollection failed. See "IsNull (OraCollection) Property".

OERROR_NOELEMENT

5197

Element does not exist for the given index.

OERROR_INVINDEX

5198

Invalid collection index is specified.

OERROR_NODELETE

5199

Delete operation is not supported for the VARRAY collection type.

OERROR_SAFEARRINVELEM

5200

Variant SafeArray cannot be created from the collection having nonscalar element types.


OraNumber Errors

Table 5-9 lists the OraNumber errors.

Table 5-9 OraNumber Errors

Constant Value Description

OERROR_NULLNUMBER

5296

Operation on NULL OraNumber object failed.


See Also:

OraNumber Object

Oracle Errors

The most recent Oracle error text is available from the LastServerErr and LastServerErrText properties of the OraSession or OraDatabase objects.

  • OraSession object

    The LastServerErr and LastServerErrText properties of the OraSession object return all errors related to connections, such as errors on the OpenDatabase method.

  • OraDatabase object

    The LastServerErr and LastServerErrText properties of the OraDatabase object return all errors related to an Oracle cursor, such as errors on the CreateDynaset, CreateSQL, and ExecuteSQL methods.

Oracle Data Control Errors

Oracle Data Control errors are specific to the Oracle data control. During the visual access of the data control, the OO4O automation server-specific errors are reported as OLE automation server errors with the error code of ODCERR_AUTOMATION. Specific Oracle Data Control error codes are retrieved from the DataErr parameter of the Error() event.

Table 5-10 lists the Oracle Data Control errors.

Table 5-10 Oracle Data Control Errors

Constant Value Description

ODCERR_INITOIP

28000

Initialization of Oracle In-Process Server failed. Check the registry for the correct location of Oracle In-Process Server.

ODCERR_OLEQE

28001

Internal error. Querying In-Process Server interface failed.

ODCERR_AUTOMATION

28003

Oracle In-Process Server error occurred.

ODCERR_NODYNASET

28007

Attempted to access Oracle Data Control before initialization.

ODCERR_FIELDINDEX

28009

Bound controls trying to access with invalid field index.

ODCERR_FIELDNAME

28013

Bound controls tried to access with an invalid field name.

ODCERR_MEMORY

28014

Internal error. Failed to allocate memory for the requested bindings from the bound control.

ODCERR_BMKTYPE

28015

Oracle Data Control does not support the requested bookmark type.

ODCERR_CONVERSION

28016

Oracle Data Control cannot convert the field value to the requested type.

ODCERR_SETSESSION

28017

Setting the session property is not allowed.

ODCERR_SETDATABASE

28018

Setting the database property is not allowed.

ODCERR_BLOBUPDATE

28019

Oracle Data Control does not update picture or raw data directly from the bound control. Use AppendChunk() method.

ODCERR_DYN_NOCACHE

28020

Recordset property cannot be set to a dynaset created with the ORADYN_NOCACHE option (bound control connected to data control often requires bidirectional navigation).

ODCERR_DYN_NOMOVEFIRST

28021

Recordset property cannot be set to a dynaset created with the ORADYN_NOMOVEFIRST option.


Troubleshooting

This topic describes common errors related to the following:

See Also:

Oracle Database Error Messages for additional information about errors

OLE Initialization or OLE Automation Errors

The most frequent cause of OLE initialization and automation errors is missing or incorrectly installed software. Ensure correct installation of the software specified. Then make sure that you have specified method and property names correctly and that you have declared all Oracle objects as type object.

Table 5-11 lists the causes and solutions for OLE errors.

Table 5-11 Causes and Solutions for OLE Errors

Possible Cause Solution

Your system does not contain the Microsoft OLE Automation or run-time, files or these files are out of date.

Make sure you have the latest versions of files such as the following installed.

  • mfc42.dll

  • oleaut32.dll

  • ole32.dll

The Oracle Objects for OLE object information was not registered in the Windows registration database.

Either reinstall Oracle Objects for OLE or run the regedt32.exe file to register information. See "Oracle Objects for OLE Redistributable Files".

Your system does not contain the Oracle Required Support Files:

  • oraclient*.dll

  • orageneric*.dll

  • oracommon*.dll

  • oracore*.dll

  • oranls*.dll

Check the OO4O readme.htm file to see what version of the Oracle Database client is required and install it.

Your system does not contain the Oracle networking product or its files are not on the PATH.

Install an Oracle networking product, or add to your PATH an environment variable that indicates the directory containing these files.

You misspelled a method or property name.

Check Oracle Objects for OLE Developer's Guide (this guide) to determine the correct spelling.

You referenced a method or property from the wrong object.

Check Oracle Objects for OLE Developer's Guide (this guide) to determine the correct object.

Your system does not contain the oraansiVER.dll file.

Reinstall Oracle Objects for OLE or add to your PATH environment variable the directory in which these files are located.

Note: VER refers to the version.


Oracle Network Errors

The most frequent cause of Oracle network errors is incorrectly specified connection information. The connection information for Oracle Objects for OLE is specified differently than when using Open Database Connectivity (ODBC). Please verify that you specified connection information correctly, and then make sure your network connection is working properly before using Oracle Objects for OLE. The appropriate Oracle network documentation contains information about testing your connection and about any Oracle networking error that you may receive.

Table 5-12 lists the Oracle network errors.

Table 5-12 Oracle Networking Errors

Possible Cause Solution

Incorrect Connect property or argument to the OpenDatabase method.

See the topics on the Connect property or the OpenDatabase method for examples.

Incorrect DatabaseName property or argument to the OpenDatabase method.

See the topics on the DatabaseName property or the OpenDatabase method for examples.

Your system does not contain the Oracle networking product.

Install Oracle networking software.


Access Violations

The most frequent cause of access violations is installing Oracle Objects for OLE while other applications are running that require the OO4O automation server, Oracle Required Support Files, or OLE. To avoid this, install Oracle Objects for OLE immediately after starting Windows and before running any other application.

Table 5-13 lists the access violations.

Table 5-13 Access Violations

Possible Cause Solution

Duplicate Oracle Objects for OLE files exist in SYSTEM directories or along the PATH.

Remove any duplicate files. The files oipVER.dll and oipVER.tlb should only be located in the ORACLE_BASE\ORACLE_HOME\bin directory.

Duplicate Oracle Required Support Files DLLs exist in the SYSTEM directories or along the PATH.

Remove any duplicate files. Typically, the Oracle Required Support Files DLLs are located in the ORACLE_BASE\ORACLE_HOME \bin directory:

  • oraclient*.dll

  • orageneric*.dll

  • oracommon*.dll

  • oracore*.dll

  • oranls*.dll

Duplicate OLE DLLs exist in the SYSTEM directories or along the PATH.

Remove any duplicate files. The OLE DLLs (listed in the OO4O File Locations section) should only be located in \system directories.