Subject: Re: PostgreSQL does not choose my indexes well
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From: Arcadio Ortega Reinoso <arcadio.ortega@gmail.com>
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Date: Thu, 23 Apr 2020 23:01:36 +0200
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El 23/4/20 a las 22:45, Tom Lane escribió:
> "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
>
>
Actually

CREATE DOMAIN cod_pk AS bigint;

create table public.tabla
(
     cod_tabla cod_pk not null,
     tabla varchar(31) not null,
     constraint pk_tabla primary key (cod_tabla)
);


Do you think is important?


Thank you very much to all