after update trigger

I need to delete a row if one of the columns is updated to be zero. I get the "mutating table error". I've heard it discussed before, but can't recall the workaround. This is more or less the idea:

	begin
		if :new.col_val = 0
			then delete tname where tname.pkey = :old.pkey;
		end if;
	end;

Anyone have a quick suggestion?

TIA,

-- 
/* Billy O'Connor                  email:  billyoc_at_iii.net
   D.P.S. Consulting, Boston MA      CIS:  74021,530
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