Managing incompatible changes for applications

Before you move an application to a new application compatibility (APPLCOMPT) level, you might need to adjust your applications for certain incompatible changes that are unrelated to use of new SQL function, and verify that they are resolved.

1. Start a trace that includes IFCID 0239 to capture package information.
   For example, issue the following START TRACE command:

   -START TRACE(ACCTG) CLASS(7,8,10)

   
2. Examine the trace output.
   IFCID 0239 field QPACFLGS contains a bit that is on if a package contains incompatibilities. If this bit is off, no incompatibilities were detected, and you can skip the rest of the steps. If this bit is on, proceed to step 3.
3. Start a trace for IFCID 0376 to report incompatibility information about the packages.
   For example, issue the following START TRACE command:

   -START TRACE(PERFM) CLASS(32) IFCID(376)

   
4. Run the application.
5. Examine the trace output.
   IFCID 0376 fields contain information about the incompatibilities. Db2 writes a single trace record for each SQL statement that is incompatible with the subsequent Db2 function level. See file prefix.SDSNIVPD(DSNWMSGS) for listings of the IFCID 0239 and 0376 trace records.
6. Revise the application to avoid any application incompatibilities.
7. Prepare the application for execution. When you bind the packages for the application, use the old APPLCOMPAT value.
8. Run the application.
9. Examine the trace output again to verify that the incompatibilities no longer exist.