Before I dig deeper into the identification, first we need to clarify what is meant with "activity". It could be almost anything going on in the database system that is related to a single database and could be both user- and system-related tasks. The important distinction is that is on the database level, not for a DB2 instance. Identification of activities deals with three questions: WHO is doing WHAT on my database and WHERE is that data located?
The WHO can be answered by looking at the connection properties such as:
- Who is the user and which group does the user belong to?
- Is the user operating in a special role?
- From where is the user connecting, does the machine have a name, is it from a specific application?
By specifying a "data tag" for a work class, it can be related to storage groups or tablespaces and their priority. This is how activity can be identified by from WHERE the data is processed.
Because multiple work classes in a work class set could identify the same activity, the individual work classes can be ordered/positioned within the set. That way a work class with several properties could pick a very specific activity whereas other activities would be mapped to more general work classes.
Using the concepts of WORKLOAD and WORK CLASS SET it is possible to identify an activity. They help to understand what is going on in the DB2 database system. It is the prerequisite for actively controlling and managing the activities in the system by assigning resources.