Subject: Re: Unexplainable execution time difference between two test
 functions...one using IF (SELECT COUNT(*) FROM...) and the other using IF
 EXISTS (SELECT 1 FROM...)
To: Hackety Man <hacketyman@gmail.com>,
 Pavel Stehule <pavel.stehule@gmail.com>,
 Pgsql Performance <pgsql-performance@lists.postgresql.org>
Cc: Robert Haas <robertmhaas@gmail.com>
References: 
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 <CAFj8pRA5sS+dxBP8ZiDLMw6KUZKtVGa476cgxe5nJ5K1n43xng@mail.gmail.com>
 <CA+1fJ+_t-gX1f9ni26mbxMUX5pv=8dB=jfhaVRK8akjCtgjBkA@mail.gmail.com>
From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Message-ID: <bd907ab8-74ea-383f-b547-0928154a11ac@2ndquadrant.com>
Date: Tue, 17 Apr 2018 22:30:47 +0200
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On 04/17/2018 04:05 PM, Hackety Man wrote:
> Hi Pavel,
> 
> Thanks for sharing that information.  I was not aware that the parallel
> query functionality was not yet fully implemented.
> 

Nothing is ever "fully implemented". There are always gaps and possible
improvements ;-)

That being said, parallelism opens an entirely new dimension of possible
plans and planning issues.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services