There are four stages to migrating an application to the Advanced
Database feature:
Change the DBM class on the application’s connection specs to the
UtyDB2AbtDatabaseManager class. Once this has been done, the
application should be able to immediately start running with the Advanced
Database feature. If problems occur, developers should check their code
to ensure it doesn’t depend upon features that the compatibility layer does
not support. These are documented above. Although the
application is no longer directly using the base database feature, it must
remain loaded in the image until after the next stage of migration.
Remove the application’s dependency on the "VisualAge: Database
ODBC" and "VisualAge: Database DB2 CLI" features, by modifying its code
to use instances of the UtyDB2SqlDescriptor class rather than the
AbtQuerySpec class. The process for doing this is outlined
in the next section. Once this has been done, the application should no
longer reference either of the AbtQuerySpec or
AbtCompoundType classes.
Change the prerequisites of the application’s VisualAge applications so
that any VisualAge application that used to be dependent upon the
AbtDbmIbmCliBaseApp application is now dependent upon the UtyDB2VAApp
application. Once this has been done, it should be possible to unload
the UtyDB2VATypeApp , AbtDbmIbmCliBaseApp, AbtDbmIbmSqldaApp, and
AbtDbmOdbcApp applications.
Note:
The UtyDB2VATypeApp application must be unloaded first, followed by the
AbtDBmIbmCLI applications and then the AbtDbmOdbcApp
Over time, the application should be gradually reworked to remove all
references to classes and methods implemented by the base database feature
and/or the UtyDB2VAApp VisualAge application. Once this has been done,
it should be possible to unload the UtyDB2VAApp and any remaining AbtDbm
VisualAge applications.