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Re: Bad perf when using DECLARE CURSOR on big table - Mailing list pgsql-performance

From Tom Lane
Subject Re: Bad perf when using DECLARE CURSOR on big table
Date
Msg-id 4008327.1742224977@sss.pgh.pa.us
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In response to Bad perf when using DECLARE CURSOR on big table  (kimaidou <kimaidou@gmail.com>)
Responses Re: Bad perf when using DECLARE CURSOR on big table
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kimaidou <kimaidou@gmail.com> writes:
> I have seen that this DECLARE has bad perf compared to a simple SQL query :

> Simple SQL query
> =====
> https://explain.dalibo.com/plan/042bc4dc2449adfe
> 96ms

> DECLARE CURSOR for the same query
> =====
> https://explain.dalibo.com/plan/bh83fc0db500a79g#
> 171 031 ms !!

Raising cursor_tuple_fraction would probably help this case.

            regards, tom lane

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