Hi
The table holds the data that flowing through your processes. E.g. the process data.
The data in IWA_TaskData can be safely deleted once the case it belongs to is in state DONE or DESTROYED.
IWA_TaskData.TaskId -> IWA_Task.TaskId, IWA_Task.CaseId -> IWA_Case.CaseId, IWA_Case.State
By default the data is not deleted after a case is DONE because of traceability.
There is another table called IWA_StartTaskData. This table stores the process data at the start of a task whereas IWA_TaskData stores the process data at the end of a task.
You can control which process data is persistently stored in the system database in the data class editor. See persistent flag in the attributes table. If an attribute is not persistent it will not be stored to the IWA_TaskData table. Note that the attribute is then null after a task element. Sometimes it is better to reload certain data again from a database than to permantly store them in process data attributes.
Hope this helps
Reto Weiss, ivyTeam Support