From: "Mike Sofen" <msofen@runbox.com>
To: "'Tom Lane'" <tgl@sss.pgh.pa.us>,
	"'Laurenz Albe'" <laurenz.albe@cybertec.at>
Cc: "'MingJu Wu'" <mingjuwu0505@gmail.com>,
	<pgsql-performance@lists.postgresql.org>
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 <43b329d274c3535c75d2fbd6912b5ae8e3e51582.camel@cybertec.at>
 <19549.1581867005@sss.pgh.pa.us>
In-Reply-To: <19549.1581867005@sss.pgh.pa.us>
Subject: RE: Partial index creation always scans the entire table
Date: Sun, 16 Feb 2020 16:43:10 -0800
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>From: Tom Lane <tgl@sss.pgh.pa.us>   Sent: Sunday, February 16, 2020 7:30
AM
>I've seen people try to do this before.  I wonder if the manual page about
partial indexes should explicitly say "don't do that". 
>	regards, tom lane

Yes please (seriously).  The utter beauty of Postgres is the flexibility and
power that its evolutionary path has allowed/created.  The tragic danger is
that the beauty is fairly easy to misapply/misuse.  Caveats in the
documentation would be very beneficial to both seasoned practitioners and
newcomers - it is quite challenging to keep up with everything Postgres and
the documentation is where most of us turn for guidance.  

And thank you Tom (and others), for your willingness to share these (and
many, many other) insights - it is so powerful when facts connect with
database reality.

Mike Sofen