Date: Fri, 25 Jun 2021 11:21:06 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: Ayub Khan <ayub.hp@gmail.com>
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: slow performance with cursor
Message-ID: <20210625162106.GM29179@telsasoft.com>
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On Fri, Jun 25, 2021 at 07:09:31PM +0300, Ayub Khan wrote:
> I am using postgresql 12 and using cursors in a stored procedure,
> executing procedure which has cursor is slowing down the call. However if I
> do not use the cursor and just execute the queries using JDBC (Java client)
> it's fast.

Is the query slower, or is it slow to transfer tuples ?
I expect there would be a very high overhead if you read a large number of
tuples one at a time.

> Is there any setting which needs to be modified to improve the performance
> of cursors. Also facing slow response with reading blobs (images) from db.
> Not an ideal way for storing images in db but this is a legacy application
> and wanted to check if there a quick tweak which can improve the
> performance while reading blob data from db.

Is the slowness between the client-server or on the server side ?
Provide some details ?

-- 
Justin