Differences between Db2 ODBC and ODBC 3.0

Several differences exist between the drivers and runtime environment of Db2 ODBC and ODBC 3.0.

Db2 ODBC is derived from the ISO Call Level Interface Draft International Standard (ISO CLI DIS) and ODBC 3.0.

If you port existing ODBC applications to Db2 for z/OS® or write a new application according to the ODBC specifications, you must comply with the specifications defined in this publication. However, before you write to any API, validate that the API is supported by Db2 ODBC and that the syntax and semantics are identical. For any differences, you must code to the APIs documented in this publication.

On the Db2 for z/OS platform, no ODBC driver manager exists. Consequently, Db2 ODBC support is implemented as a CLI/ODBC driver/driver manager that is loaded at run time into the application address space.

The Db2 for Linux®, UNIX, and Windows support for CLI executes on Windows and AIX® as an ODBC driver, loaded by the Windows driver manager (Windows environment) or the Visigenic driver manager (UNIX platforms). In this context, Db2 ODBC support is limited to the ODBC specifications. Alternatively, an application can directly invoke the CLI application programming interfaces (APIs) including those not supported by ODBC. In this context, the set of APIs supported by Db2 for Linux, UNIX, and Windows is referred to as the "Call Level Interface."

The use of Db2 ODBC in this publication refers to Db2 for z/OS support of Db2 ODBC unless otherwise noted.