Enabling default application compatibility with function level 500 or higher

The APPLCOMPAT subsystem parameter specifies the default value of the APPLCOMPAT bind option. Before function level 500 or higher is activated, the APPLCOMPAT subsystem parameter must be set to function-level or V10R1. These settings ensure that existing SQL applications are bound for compatibility with the earlier release by default.

Before you begin

  1. Activate function level 500 or higher, as described in Activating Db2 13 function level 500 or higher.
  2. For any packages that need to continue running at a lower level, bind or rebind them and explicitly specify the APPLCOMPAT bind option. For more information, see Controlling the Db2 application compatibility level.
  3. Take the following precautions to ensure that applications are ready to run at the higher application compatibility level by default.
    • Identify and resolve all application incompatibilities of the higher level, as described in Managing application incompatibilities.
    • Rebind any packages that must continue to run at the lower application compatibility level and explicitly specify the APPLCOMPAT bind option for that level.

About this task

After all applications are ready to run at a higher application compatibility level or explicitly bound at a lower level, you can increase the APPLCOMPAT subsystem parameter value to bind packages at a higher application compatibility level by default.

The APPLCOMPAT subsystem parameter specifies the default value to use when the APPLCOMPAT bind option is not specified in a BIND command, or the APPLCOMPAT value is not specified or stored in the Db2 catalog for a REBIND command. Its value does not prevent specific applications from running at higher application compatibility levels. For more information, see APPL COMPAT LEVEL field (APPLCOMPAT subsystem parameter).

Procedure

To enable default application compatibility with the current function level:

  1. Change the APPLCOMPAT subsystem parameter setting. Set the value to V13R1M500 or the equivalent higher active function-level value.
    You can complete this step as described in Updating subsystem parameter and application default values, or by modifying your customized copy of the DSNTIJUZ job.
    The format is VvvRrMmmm, where vv is the version, r is the release, and mmm is the modification level. For example, V13R1M506 identifies function level 506. For a list of all available function levels in Db2 13, see Db2 13 function levels. See the activation details for each function level for a summary the new features that are controlled by the corresponding application compatibility level.
  2. Run the first two job steps of DSNTIJUZ to rebuild your subsystem parameter (DSNZPxxx) module.
  3. Use the -SET SYSPARM command or restart Db2.

Results

Future bind and rebind operations set the application compatibility level of the package to the APPLCOMPAT subsystem parameter value, if the APPLCOMPAT bind option is not specified. Packages that are bound or rebound at the higher level can begin use of SQL capabilities introduced at that level.