oracle odbc driver configuration fetch buffer size

Oracle Odbc Configuration Fetch Buffer Size Driver Manager Through

The change has been done to increase the performance of ODBC driver for catalog APIs.

The applications source code does not have to be recompiled for each data source.

A database driver links the application to a specific data source.

A database driver is a dynamic-link library that an application can invoke on demand to gain access to a particular data source.

Therefore, the application can access any data source for which a database driver exists.

Oracle Odbc Configuration Fetch Buffer Size Driver Manager Through

The model begins with an ODBC application making a call to the Driver Manager through the ODBC application program interface (API).

The Driver Manager can be either the Microsoft Driver Manager or the unixODBC Driver Manager.

Still using the ODBC API, the Driver Manager makes a call to the ODBC Driver.

The ODBC Driver accesses the database over a network communications link using the database API.

Figure 21-1 shows an ODBC application accessing three separate databases.

When the results are returned from the data source, the Oracle ODBC Driver translates them back to ODBC SQL syntax.

See Oracle Database PLSQL Language Reference and Oracle Database SQL Language Reference for information about creating 32 KB columns.

After error translation is registered, then ODBC application users can enable this option, SQLTranslateErrors T, to receive native errors according to their registration.

This support eases any third party ODBC application, which migrated to Oracle and wants to use this same functionality that was provided by their previous vendors.

See Oracle Call Interface Programmers Guide for more information about auto increment.

This property is read-only and returns SQLTRUE if the column is auto increment; otherwise, it returns SQLFALSE.

See Table 21-7 in Section 21.4.11.2, Implementation of ODBC API Functions, and (vVS.85).aspx for more information.

To do this, the maximum size of LONG data ( MaxLargeData ) must be set in the registry on Windows (you also must add the registry key MaxLargeData in the data source name (DSN)), and set this manually in the odbc.ini file on UNIX platforms.

This enhancement improves the performance of Oracle ODBC driver up to 10 times, depending on the MaxLargeData size set by the user.

The maximum value for MaxLargeData that you can set is 64 KB (65536 bytes).

If your database has LONG or LONG RAW data that is greater that 65536 bytes, then set MaxLargeData to 0 (the default value), which causes single-row fetch and fetches complete LONG data.

If you pass a buffer size less than the MaxLargeData size in nonpolling mode, a data truncation error occurs if the LONG data size in the database is greater than the buffer size.

To enable this option, set the value of UseOCIDescribeAny in odbc.ini to T (True), default value is F (False), on UNIX platforms, and through the registry on Windows.

Oracle Odbc Driver Configuration Fetch Buffer Size