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Date: Mon, 24 Sep 2018 14:30:44 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: legrand legrand <legrand_legrand@hotmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Explain is slow with tables having many columns
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On Mon, Sep 24, 2018 at 12:22:28PM -0700, legrand legrand wrote:
> Hello,
> I have found that explain on tables with many (hundreds) columns
> are slow compare to nominal executions.

See also this thread from last month:

https://www.postgresql.org/message-id/flat/CAEe%3DmRnNNL3RDKJDmY%3D_mpcpAb5ugYL9NcchELa6Qgtoz2NjCw%40mail.gmail.com

Justin