select cola1,cola2,colb1,colb2 from tablea left outer join tableb on cola1 = colb1 where colb1 is null
Sample query.
Two points:-
This could be more accurate if you could provide table structure (see first link in my signature).
You need to understand this if you want to enhance your skills this linkhttp://msdn.microsoft.com/en-gb/library/ms187518(v=sql.105).aspx provides more information. The same information is also in Books on line
-------------------------------Posting Data Etiquette - Jeff Moden [/url]Smart way to ask a question
There are naive questions, tedious questions, ill-phrased questions, questions put after inadequate self-criticism. But every question is a cry to understand (the world). There is no such thing as a dumb question. ― Carl Sagan
I would never join a club that would allow me as a member - Groucho Marx