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From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: johannes graën <johannes@selfnet.de>
Cc: Pavel Stehule <pavel.stehule@gmail.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: performance drop after upgrade (9.6 > 10)
Date: Tue, 24 Oct 2017 18:17:15 +0200
Message-ID: <20171024161715.admzmcnbpagm6yvf@alvherre.pgsql> (raw)
In-Reply-To: <CA++JNSfTEifSiBq73zpGCQuDNGr9yYcjmkx_=LtAbnadKLY_vg@mail.gmail.com>
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johannes graën wrote:
> Hi Pavel, *,
> 
> you were right with ANALYZing the DB first. However, even after doing
> so, I frequently see Seq Scans where an index was used before. This
> usually cooccurs with parallelization and looked different before
> upgrading to 10. I can provide an example for 10 [1], but I cannot
> generate a query plan for 9.6 anymore.

https://wiki.postgresql.org/wiki/Slow_Query_Questions

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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