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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
        Bruce Momjian <bruce@momjian.us>,
        pgsql-committers <pgsql-committers@lists.postgresql.org>
Subject: Re: pgsql: doc: clarify recursion internal behavior
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
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Robert Haas <robertmhaas@gmail.com> writes:
> On Thu, Sep 8, 2022 at 7:24 AM Peter Eisentraut
> <peter.eisentraut@enterprisedb.com> wrote:
>> On 03.09.22 03:58, Bruce Momjian wrote:
>>> +    While <literal>RECURSIVE</literal> allows queries to be specified
>>> +    recursively, internally all queries are evaluated iteratively.

>> Is that true?  Surely there is some recursive behavior in the executor.

> I haven't read the patch, but I think the claim shown here is correct.

I'd be happier if it read "such queries" instead of "all queries".
The latter is an extremely broad claim, and you have to ignore cases
like recursive SQL functions in order to even argue it's true.

			regards, tom lane