Re: Set enable_seqscan doesn't take effect? - Mailing list pgsql-hackers

From David G. Johnston
Subject Re: Set enable_seqscan doesn't take effect?
Date
Msg-id CAKFQuwZhY1wA65gjDf10VK5SzzYe2+c_RV1SEEs_-ippuThBZg@mail.gmail.com
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In response to Set enable_seqscan doesn't take effect?  (jacktby jacktby <jacktby@gmail.com>)
Responses Re: Set enable_seqscan doesn't take effect?
List pgsql-hackers
On Wednesday, September 27, 2023, jacktby jacktby <jacktby@gmail.com> wrote:
postgres=# SET enable_seqscan = off;
SET
postgres=# explain select * from t;
                               QUERY PLAN                               
-------------------------------------------------------------------------
 Seq Scan on t  (cost=10000000000.00..10000000023.60 rows=1360 width=32)

It wouldn’t cost 10billion to return the first tuple if that setting wasn’t working.

That is the “discouragement” the documentation is referring to.

I do agree the wording in the docs could be improved since it is a bit self-contradictory and unspecific, but it is explicitly clear a plan with sequential scan can still be chosen even with this set to off.

David J.

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