Re: Oracle_FDW table performance issue - Mailing list pgsql-performance

From aditya desai
Subject Re: Oracle_FDW table performance issue
Date
Msg-id CAN0SRDFyB5=kRayXtPiA=9LQqPu6nvXJ0OeLzoQQUSuky74cag@mail.gmail.com
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In response to Re: Oracle_FDW table performance issue  (Justin Pryzby <pryzby@telsasoft.com>)
List pgsql-performance
Hi Justin,
Sorry unable to send a query plan from a closed network. Here the stats are updated on the Oracle table. 


It seems like when joining the local tables it is not filtering data on Oracle and bringing data to postgres. It is filtering when we actually pass the values.


Regards,
Aditya.

On Mon, Jul 11, 2022 at 5:43 PM Justin Pryzby <pryzby@telsasoft.com> wrote:
On Mon, Jul 11, 2022 at 05:38:34PM +0530, aditya desai wrote:
> Hi,
> I have one Oracle fdw table which is giving performance issue when joined
> local temp table gives performance issue.
>
> select * from oracle_fdw_table where transaction_id in ( select
> transaction_id from temp_table) ---- 54 seconds. Seeing HASH SEMI JOIN  in
> EXPLAIN PLAN. temp_table has only 74 records.

You'd have to share the plan

https://wiki.postgresql.org/wiki/Slow_Query_Questions

Do the tables have updated stats ?

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