Re: Counting all rows
От | Stefan Arentz |
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Тема | Re: Counting all rows |
Дата | |
Msg-id | adf34c300706230615j4763748dn9e1dae2cb5c2524c@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: Counting all rows (Andreas Kretschmer <akretschmer@spamfence.net>) |
Список | pgsql-sql |
On 6/23/07, Andreas Kretschmer <akretschmer@spamfence.net> wrote: > Stefan Arentz <stefan.arentz@gmail.com> schrieb: > > > I need to get statistics from a bunch of tables. Simply the number of > > records in them. > > > > The query plan looks like this: > > > > => explain select count(id) from stuff; > > QUERY PLAN > > ------------------------------------------------------------------- > > Aggregate (cost=1629.69..1629.70 rows=1 width=8) > > -> Seq Scan on stuff (cost=0.00..1517.75 rows=44775 width=8) > > > > The sequential scan kind of worries me. Is there a better/faster way to do > > this? > > Yes. > > A "select count(*) from foo;" enforces a seq. scan. Solutions for this > are discussed here: http://www.varlena.com/GeneralBits/120.php Thank you Andreas. That is exactly what I was looking for. S.
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