Message-ID: <1bbde4f2929ef4f5cf145ccffaca3d3f6e27a7bd.camel@cybertec.at>
Subject: Re: LIMIT OFFSET with DB view vs plain SQL
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Raj Gandhi <raj01gandhi@gmail.com>, pgsql-admin@postgresql.org
Date: Fri, 29 Mar 2019 14:53:10 +0100
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Raj Gandhi wrote:
> I’m using LIMIT offset with DB view. Looks like query planner is applying the LIMIT for DB view at the end after processing all rows.
> When running same SQL that was used to create the DB view, LIMIT is applied earlier so the query is much faster.
>  
> Explain plan using DB view
> https://explain.depesz.com/s/gzjQ
>  
> Explain plan using raw SQL
> https://explain.depesz.com/s/KgwO
>  
> In both tests LIMIT was 100 with offset  = 0.
> Is there any way to force DB view to apply limit earlier?

Please show

- the view definition
- the query on the view
- the query without the view

Yours,
Laurenz Albe
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