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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrei Lepikhov <lepihov@gmail.com>
cc: pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Avoid mislabeling of lateral references when pulling up a
 subque
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Comments: In-reply-to Andrei Lepikhov <lepihov@gmail.com>
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Andrei Lepikhov <lepihov@gmail.com> writes:
> Pardon the noise, but I'm curious why the optimiser must choose NestLoop 
> in the case of lateral reference.

To pass down the current outer row's value of the lateral reference.

> It would be nice to provide alternatives. Because now we have some 
> corner cases.

That's a fairly bizarre case, and I'm not at all convinced that
the old plan was correct.

			regards, tom lane