public inbox for [email protected]  

help / color / mirror / Atom feed

From: Laurenz Albe <[email protected]>
To: Durgamahesh Manne <[email protected]>
To: pgsql-general <[email protected]>
Subject: Re: Regarding query optimisation (select for update)
Date: Tue, 15 Jul 2025 14:43:59 +0200
Message-ID: <[email protected]> (raw)
In-Reply-To: <CAJCZko+fiU+=NSEGY7d7YMpFxg_jANpiO-LU6ur+yqRc_Ej6eQ@mail.gmail.com>
References: <CAJCZko+fiU+=NSEGY7d7YMpFxg_jANpiO-LU6ur+yqRc_Ej6eQ@mail.gmail.com>

On Tue, 2025-07-15 at 15:40 +0530, Durgamahesh Manne wrote:
> We are facing issues with slow running query 
>    SELECT betid, versionid, betdata, processed, messagetime, createdat, updatedat
>    FROM praermabetdata where processed = 'false'
>    ORDER BY betid, versionid LIMIT 200 OFFSET 0 FOR UPDATE;  
> 
>                                                          QUERY PLAN
> --------------------------------------------------------------------------------------------------------------------------------
>  Limit  (cost=0.28..1.89 rows=1 width=78)
>    ->  LockRows  (cost=0.28..1.89 rows=1 width=78)
>          ->  Index Scan using idx_praermabetdata_processed_betid_versionid on praermabetdata  (cost=0.28..1.88 rows=1 width=78)
>                Index Cond: (processed = false)
> 
> image.png
> 
> Do we have any alternative way to improve the performance?
> Sometimes processed column use true as well as false 

Please provide EXPLAIN (ANALYZE, BUFFERS) output and use "log_lock_waits"
to see if you are hanging behind locks for a longer time.

Yours,
Laurenz Albe

view thread (6+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: Regarding query optimisation (select for update)
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox