Extracting data from CATSDB

Dear All,

I have a task of extracting the data from CATSDB depending upon the selection parameters. The selection screen will contain the Personnel number field and BEGDA and ENDDA fields. Now, all those PERNRs have to be extracted from CATSDB within the period of BEGDA and ENDDA. But my problem is I dont find any BEGDA and ENDDA fields in CATSDB database table. so, how to go abt it?

Thanks,

sss