Re: Why Postgres doesn't use TID scan? - Mailing list pgsql-performance

From Andrew Gierth
Subject Re: Why Postgres doesn't use TID scan?
Date
Msg-id 87bm5hwxy2.fsf@news-spur.riddles.org.uk
Whole thread Raw
In response to Re: Why Postgres doesn't use TID scan?  (Vladimir Ryabtsev <greatvovan@gmail.com>)
Responses Re: Why Postgres doesn't use TID scan?  (Vladimir Ryabtsev <greatvovan@gmail.com>)
List pgsql-performance
>>>>> "Vladimir" == Vladimir Ryabtsev <greatvovan@gmail.com> writes:

 Vladimir> I can't believe it.
 Vladimir> I see some recommendations in Internet to do like this

well, 90% of what you read on the Internet is wrong.

 Vladimir> Did it really work in 2011? Are you saying they broke it?
 Vladimir> It's a shame...

The method in that SO link does work, it's just slow. The workaround is
to do it like this instead:

delete from mytable
 where ctid = any (array(select ctid from mytable
                          where ...
                          order by ...
                          limit 1000));

But of course that's still an ugly hack.

-- 
Andrew (irc:RhodiumToad)


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