From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Stephen Frost <sfrost@snowman.net>, Thomas Kellerer <shammat@gmx.net>,
        "pgsql-performance@lists.postgresql.org"
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Subject: Re: PostgreSQL does not choose my indexes well
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Thu, 23 Apr 2020 13:36:15 -0700"
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Date: Thu, 23 Apr 2020 16:45:42 -0400
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> I noticed that too...I suspect its related to the ANALYZE result:

> Index Scan using idx_tabla_entidad on entidad (cost=0.56..51121.41
> rows=1405216 width=20) (actual time=0.037..242.609 rows=1409985 loops=1)
>    Index Cond: ((cod_tabla)::bigint = 4)

Yeah, that *strongly* suggests that cod_tabla isn't really bigint.
I'm wondering about domains, for instance.

			regards, tom lane