Need help writing a trigger

        I have 2 tables involved in a trigger (currently on Interbase). The trigger goes something like this ...

create trigger test
after delete on A
for each row

begin
update B
set status = 'X'
where code = (select code from A tab_a

	where tab_a.code = :old.code
	and tab_a.mydate <= sysdate);

end;

code is the primary key on B, but not on A

        Obviously, this trigger causes errors (table mutating). I'm wondering if there is a smart way around this. I cannot re-engineer the tables.

--

kshave_at_minet.gov.mb.ca