The results for GT Subset are different for DB2 table which includes generated/computed columns which datatype is timestamp as:
When using "Build SQL Insert Script", then getting all the columns in "insert" and "select" dml sentences .
When using "Workflow,Save Workflow Subset", then not getting columns which are generated/computed columns in "select" dml.
It seems that when using "Workflow,Save Workflow Subset" is a defect.
Release : 4.8
Component : CA Test Data Manager
This "Workflow,Save Workflow Subset" part does not transfer the data for the columns which can be computed (like generated/computed column), because values of these columns will be computed again in the target table. Then this works as designed.