Feedback-ID: ia2694551:Fastmail
Date: Tue, 17 Sep 2024 10:28:45 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: yudhi s <learnerdatabase99@gmail.com>
Cc: pgsql-general <pgsql-general@lists.postgresql.org>
Subject: Re: update faster way
Message-ID: <202409170828.kioipz3ryfof@alvherre.pgsql>
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On 2024-Sep-14, yudhi s wrote:

> Hello,
> We have to update a column value(from numbers like '123' to codes like
> 'abc' by looking into a reference table data) in a partitioned table with
> billions of rows in it, with each partition having 100's millions rows.

Another option is to not update anything, and instead create a view on
top of the partitioned table (joined to the reference table) that
returns the reference value instead of the original number value from
the column; when the application wants to receive those reference
values, it queries the view instead of the partitioned table directly.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
"I think my standards have lowered enough that now I think 'good design'
is when the page doesn't irritate the living f*ck out of me." (JWZ)