Is this statement correctly Deleting row-by-row

Question

Before i delete a parent table, i want to delete the child table. The parent table's primary key is a composite key having 3 columns.
So i need a DELETE like the following
DELETE FROM Child_Table1
where
    pkCol1,pkCol2,pkCol3=(SELECT pkCol1, pkCol2,pkCol3 FROM Parent_table WHERE curr_trk_code=40);Since the above Statement is not valid I am thinking of changing it to
DELETE FROM Child_Table1
where
    pkCol1 in (SELECT pkCol1 FROM Parent_table WHERE curr_trk_code=40)
    and
        pkCol2 in (SELECT pkCol2 FROM Parent_table WHERE curr_trk_code=40)
        and
        pkCol3 in   ((SELECT pkCol3 FROM Parent_table WHERE curr_trk_code=40);Is this DELETE correctly deleting each row in Child_Table1 based on the Composite Primary key of the parent table?
This post is related to
Purging records from table with Child tables
Edited by: M.Everett on Nov 14, 2008 1:10 AM
Edited by: M.Everett on Nov 14, 2008 1:14 AM

Answer 1

Does it not work like this...
DELETE FROM Child_Table1
where
    (pkCol1,pkCol2,pkCol3)=(SELECT pkCol1, pkCol2,pkCol3 FROM Parent_table WHERE curr_trk_code=40);i.e. include brackets around your first 3 comparison columns