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Re: Inner Join of the same table - Mailing list pgsql-performance

From Tom Lane
Subject Re: Inner Join of the same table
Date
Msg-id 20384.1155676382@sss.pgh.pa.us
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In response to Re: Inner Join of the same table  (Sebastián Baioni <sebaioni-postgresql@yahoo.com.ar>)
Responses Re: Inner Join of the same table  (Sebastián Baioni <sebaioni-postgresql@yahoo.com.ar>)
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=?iso-8859-1?q?Sebasti=E1n=20Baioni?= <sebaioni-postgresql@yahoo.com.ar> writes:
>  8                    ->  GroupAggregate  (cost=0.00..37348395.05 rows=3951 width=25) (actual
> time=130.000..2629617.000 rows=254576 loops=1)
>  9                          ->  Index Scan using uesapt001 on APORTES  (cost=0.00..37301678.64
> rows=9339331 width=25) (actual time=110.000..2520690.000 rows=9335892 loops=1)

Given the relatively small estimated number of group rows, I'd have
expected the thing to use a seqscan and HashAggregate for this part.
Do you have enable_hashagg turned off for some reason?  Or enable_seqscan?

            regards, tom lane

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