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Re: Hash Right join and seq scan - Mailing list pgsql-performance

From Tomas Vondra
Subject Re: Hash Right join and seq scan
Date
Msg-id a757dc17-2339-446c-b59c-bd0d1efb3aca@enterprisedb.com
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In response to Re: Hash Right join and seq scan  (James Pang <jamespang886@gmail.com>)
Responses Re: Hash Right join and seq scan
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Hi James,

I think it'd be much easier to help you with investigating this issue if
you shared the actual queries, and the full EXPLAIN ANALYZE output both
with and without disabled hashjoin. Or even better, share a script that
reproduces the issue (creates tables, loads data, runs the queries).

BTW you suggested each partition has ~250k rows, but the explain plan
snippet you shared does not seem to be consistent with that - it only
shows 2500-5000 rows per partition. If you run ANALYZE on the table,
does that change the plan?

regards

-- 
Tomas Vondra
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

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