I have 2 tables. GTable (GId, GText) CTable (CId, GId, CText)
I would like to delete row from GTable when there are no rows in CTable that refer to GTable.
For example. If there are 2 rows in CTable with GId=4 no action.
But if there are 0 rows with GId=5 I would like to delete from GTable the row GId=5.
How is best to do this?