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From: "Fred." <ghrno-google@yahoo.com>
Newsgroups: comp.databases.ms-sqlserver
Subject: Non-Relating Join Criteria
Date: Wed, 2 Nov 2011 06:53:47 -0700 (PDT)
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Xref: x330-a1.tempe.blueboxinc.net comp.databases.ms-sqlserver:773

Transact SQL apparently supports one-sided critera, 
such as the "a.SEL=15" in (1) below. in the join
expression. I would expect that both (1) and (2)
would return the same result set, and the examples
I have tried match this expectation.

My question is whether or not there can be a strong
reason to prefer one over the other, such as impact
on the order of evaluation.

CREATE TABLE a (APK int PRIMARY KEY, SEL int, ... )
CREATE TABLE b (BPK int PRIMARY KEY, AFK int, ... )

(1) SELECT ... FROM a INNER JOIN b 
    ON a.APK=b.AFK AND a.SEL=15

(2) SELECT ... FROM a INNER JOIN b 
    ON a.APK=b.AFK
    WHERE a.SEL=15

Fred.