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From: yoshi@nocusuhs.nnmc.navy.mil (Dojun Yoshikami)
Newsgroups: comp.databases
Subject: SQL Differences Question
Keywords: set differences, SQL
Message-ID: <1991Apr17.133725.25499@nocusuhs.nnmc.navy.mil>
Date: 17 Apr 91 13:37:25 GMT
Organization: National Naval Medical Center
Lines: 26


Question for all you SQL'er's,

How can one get the difference between two sets?  I have two tables (s, and t)
as follows:

S:		T:
-----		-----
1		1
2		3
3		7

What I would like to get is all S's that are not in T, i.e. 2 in this example.
I know there is a set algebraic operator (difference) to get this, but I'm not
sure how to get this in SQL. 

(There's gotta be a way to do this!  It's a relational algebraic operation which
should be easily done!)

DY ;-)

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D M Yoshikami  :-) ;-) :-) | Internet: yoshikami@usuhsb.ucc.usuhs.nnmc.navy.mil
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