Neben der Base-Release werden neue Funktionen und Erweiterungen in s.g. Function Levels zur Verfügung gestellt. Sie bündeln PTF’S zu Produkterweiterungen und bauen aufeinander auf. Zur Zeit (Nov. 2018) stehen für Db2 12 for z/OS folgende Function Levels zur Verfügung:

Function level 503 (activation enabled by APAR PH00506)
Function level 503 introduces support for IBM Db2 AI for z/OS, replication of system-period temporal tables and generated expression columns, a change to temporal auditing support for temporal data, and a new console message that indicates when catalog levels or function levels change.

Function level 502 (activation enabled by APAR PI95511)
Function level 502 introduces management of key labels for z/OS DFSMS data set encryption and explicit casting of numeric values to GRAPHIC or VARGRAPHIC.

Function level 501 (activation enabled by APAR PI70535)
Function level 501 introduces the LISTAGG built-in function, which produces a list of all values in a group.

Function level 500 (activated at Db2 12 installation or after migration)
Function level function level 500 (V12R1M500) represents the first opportunity for applications to take advantage of most new capabilities in the initial Db2 12 release, including new SQL capabilities and subsystem parameter settings. In many respects, function level 500 is analogous to new-function mode in previous releases.

Function level 100 (activated by migration to Db2 12)
In function level 100 (V12R1M100), Db2 runs on Db2 12 code, and virtual storage and optimization enhancements in the initial Db2 12 release become available. However, most new function, including and subsystem parameter changes and new SQL capabilities remain disabled. In many respects, function level 100 is analogous to conversion mode in previous Db2 releases.