Let's say I have two tables A and B, each of which has an integer ID
column. I want to find ID values that occur in A but not B. The
first query I came up with was:
SELECT ID FROM A WHERE NOT EXISTS (SELECT * FROM B WHERE B.ID = A.ID);
but I get a syntax error. My next try,
SELECT ID FROM A WHERE ID NOT IN (SELECT ID FROM B);
works and is probably more efficient, but I'm just curious what's
wrong with the first one.
--
James W. Walker, ScriptPerfection Enterprises, Inc.
<http://www.write-brain.com/>
