How work classes, work class sets, work actions, and work action sets work together and are associated with other DB2 objects

Work classes and work actions work together to apply specific actions to specific activity types. The best way to describe how this works is through an example.

The following diagram shows a high-level view of how work classes, work class sets, work actions, and work action sets work together and are associated with other DB2® objects.

Figure 1. Overview of work action sets and work class sets

In the diagram, some database activities are mapped, through workload WL1, workload WL3, and the default user workload, SYSDEFAULTUSERWORKLOAD, to the service superclass SS1. Because work action set WASDB is applied to the database, all activities that enter the database (regardless of the workload) and that are classified as either the WC_DML or WC_LOAD work class will have the work actions in the WASDB work action set applied to them. That is, activities with the DML work type are counted, and activities with the LOAD work type have activity data collected for them and written to an active event monitor (if one is available).

The work action set WASSSC1 is applied to the service superclass SS1. Any activities that are assigned to the default user workload, the WL1 workload, or the WL3 workload, and that fall under the WC_DML work class and the WC_LOAD work class will also have the WA_MAP_DML and WA_MAP_LOAD work actions applied to them, because those workloads direct work to the SS1 service superclass. That is, activities with a work type of LOAD will be mapped to the SSC1 service subclass by the WA_MAP_LOAD work action, and activities with a work type of DML will be mapped to the SSC2 service subclass by the WA_MAP_DML work action.

Activities that are assigned to the WL2 workload are mapped directly to a service subclass (SSC3). When a workload maps activities directly to a service subclass, no work actions from the work action set WASSSC1 are applied to those activities. However, because WASWL2 is applied to WL2, any activities assigned to WL2 and fall under WL_LOAD will have work actions in the WASWL2 work action set applied to the. That is, LOAD activities will not be allowed to be run, due to the PREVENT EXECUTION work action.