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Re: Non-Relating Join Criteria

From Hugo Kornelis <hugo@perFact.REMOVETHIS.info.INVALID>
Newsgroups comp.databases.ms-sqlserver
Subject Re: Non-Relating Join Criteria
Date 2011-11-02 15:08 +0100
Message-ID <ekj2b71idt43lo3n8m0hhmtkgrvc00jgcp@4ax.com> (permalink)
References <12431962.894.1320242027343.JavaMail.geo-discussion-forums@yqbl36>

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Hi Fred,

>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.

No. Order of evaluation can and will be shuffled by the optimizer if
that can improve performance.

The only reason for using one and not the other is readability of the
query.

Note, though, that for OUTER JOINs, the two queries are NOT
equivalent!
-- 
Hugo Kornelis, SQL Server MVP
My SQL Server blog: http://sqlblog.com/blogs/hugo_kornelis

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Thread

Non-Relating Join Criteria "Fred." <ghrno-google@yahoo.com> - 2011-11-02 06:53 -0700
  Re: Non-Relating Join Criteria Hugo Kornelis <hugo@perFact.REMOVETHIS.info.INVALID> - 2011-11-02 15:08 +0100
  Re: Non-Relating Join Criteria "Bob Barrows" <reb01501@NOyahooSPAM.com> - 2011-11-02 09:10 -0500

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