Re: Use of index in 7.0 vs 6.5

Поиск
Список
Период
Сортировка
От Bruce Momjian
Тема Re: Use of index in 7.0 vs 6.5
Дата
Msg-id 200005251511.LAA21178@candle.pha.pa.us
обсуждение исходный текст
Ответ на RE: Use of index in 7.0 vs 6.5  ("Mikheev, Vadim" <vmikheev@SECTORBASE.COM>)
Ответы Re: Use of index in 7.0 vs 6.5  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-sql
[ Charset ISO-8859-1 unsupported, converting... ]
> > For example we could count up distinct values for the first 
> > column of an index by scanning its index relation.
> 
> Oracle has index keys distribution page... And we have near empty
> meta-page for each index AM... And backend reads this page for
> each insert...

That certainly would make sense.  We have hesitated to gather more
statistics because of the time involved.  Fuller statistics on just the
indexed columns could be a big win and be done fairly quickly because
the rows are already sorted in the index.

--  Bruce Momjian                        |  http://www.op.net/~candle pgman@candle.pha.pa.us               |  (610)
853-3000+  If your life is a hard drive,     |  830 Blythe Avenue +  Christ can be your backup.        |  Drexel Hill,
Pennsylvania19026
 


В списке pgsql-sql по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Use of index in 7.0 vs 6.5
Следующее
От: Jeff Hoffmann
Дата:
Сообщение: Re: Use of index in 7.0 vs 6.5