Message-ID: <c9087811007d427467ec3725180cccd153f65bd7.camel@cybertec.at>
Subject: Re: Performance Issue with Hash Partition Query Execution in
 PostgreSQL 16
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Ramakrishna m <ram.pgdb@gmail.com>, pgsql-general@lists.postgresql.org
Cc: ravisql09@gmail.com
Date: Wed, 06 Nov 2024 19:23:11 +0100
In-Reply-To: <CAG-eXHJ+KbQ8_k-jKSGZU9V6HkLKU2Jqz7nYMYGhHuC-Zqm7qQ@mail.gmail.com>
References: 
	<CAG-eXHJ+KbQ8_k-jKSGZU9V6HkLKU2Jqz7nYMYGhHuC-Zqm7qQ@mail.gmail.com>
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On Wed, 2024-11-06 at 22:43 +0530, Ramakrishna m wrote:
> One of the queries, which retrieves a single record from a table with 16 =
hash partitions,
> is taking more than 10 seconds to execute. In contrast, when we run the s=
ame query manually,
> it completes within milliseconds.

If I read your file right, the slow execution has an additional "LIMIT 55".
That can make a difference.

In general, you can use auto_explain to get the execution plan of the slow =
query.

Yours,
Laurenz Albe