From: Tom Lane <tgl@sss.pgh.pa.us>
To: Gunther Schadow <raj@gusw.net>
cc: Justin Pryzby <pryzby@telsasoft.com>,
        pgsql-performance@lists.postgresql.org
Subject: Re: When you really want to force a certain join type?
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Comments: In-reply-to Gunther Schadow <raj@gusw.net>
	message dated "Thu, 29 Dec 2022 02:31:59 -0500"
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Date: Thu, 29 Dec 2022 02:52:10 -0500
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Gunther Schadow <raj@gusw.net> writes:
> Also, why even use the RECURSIVE keyword, DB2 didn't need it, and the 
> query analyzer should immediately see the recursion, so no need to have 
> that keyword.

Our reading of the SQL spec is that it's required.  The scope of
visibility of CTE names is different depending on whether you
write RECURSIVE or not, so it's not a question of "the query analyzer
should see it": the analyzer is required NOT to see it.

DB2 generally has a reputation for agreeing with the spec,
so I'm surprised to hear that they're not doing this per spec.

			regards, tom lane