Re: ANALYZE after CREATE TABLE AS SELECT... - Mailing list pgsql-general

From Semyon Reyfman
Subject Re: ANALYZE after CREATE TABLE AS SELECT...
Date
Msg-id 010901d05237$109ba8a0$31d2f9e0$@therealauthority.com
Whole thread Raw
In response to Re: ANALYZE after CREATE TABLE AS SELECT...  (David Steele <david@pgmasters.net>)
List pgsql-general
This is exactly my situation.

Thanks.

Semyon Reyfman

-----Original Message-----
From: pgsql-general-owner@postgresql.org
[mailto:pgsql-general-owner@postgresql.org] On Behalf Of David Steele
Sent: Thursday, February 26, 2015 8:19 PM
To: Tom Lane; Semyon Reyfman
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] ANALYZE after CREATE TABLE AS SELECT...

On 2/26/15 2:05 PM, Tom Lane wrote:
> "Semyon Reyfman" <sreyfman@therealauthority.com> writes:
>> When I create a table with "CREATE TABLE name AS SELECT." statement
>> and immediately afterward use this new table in a query does it make
>> sense to run ANALYZE on the new table in between?
>
> Yes.

Yes.  And to be more specific - vacuum cannot see tables that have been
created in a transaction, so you should always analyze tables that you
intend to read in the same transaction where you created them.

Even if you do commit before reading there is a race condition with vacuum,
so it's best to analyze.

Bonus tip: the same is true for any temp tables you might create.  More so,
since vacuum will never see them at all.

--
- David Steele
david@pgmasters.net




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