Finding entries not in table..differnce?

I need to write a quick function that tells me all of the entriles in
table that are not in table2.

The tables are copies of each other, but 1 has been updated. I know
this is easy, but I am running on little sleep :)

I want to due something like

select prodlang.prodlsku from prodland,prodlang2 WHERE prodlang.prodlsku
!= prodlang2.prodlsku

But of course I would get every record, several times since at some
point the sku does not equal another sku.

I tried !!= (NOT IN) but it did not like that at all, since sku is a
char field.

I am running an older version of postgress on this server, I do not know
if that is important.

--
Zot O'Connor

http://www.ZotConsulting.com
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