Re: Why is UseDeclareFetch so slow?
От
David Gardner
Тема
Re: Why is UseDeclareFetch so slow?
Дата
Msg-id
46828A2E.6020201@gardnerit.net
Ответ на
Re: Why is UseDeclareFetch so slow? (Rainer Bauer)
Список
Дерево обсуждения
Why is UseDeclareFetch so slow? Rainer Bauer <usenet@munnin.com>
Re: Why is UseDeclareFetch so slow? Hiroshi Inoue <inoue@tpf.co.jp>
It has been my experience, which is largely with Access as a client, already attempts to perform similar optimizations to my queries. Often Access will take a query like: SELECT * FROM PersonTbl; and turn it into: SELECT * FROM PersonTbl WHERE "PersonID" = 10566 OR "PersonID" = 10568 OR "PersonID" = 10365 OR "PersonID" = 10705 OR "PersonID" = 10390 OR "PersonID" = 10391 OR "PersonID" = 10392 OR "PersonID" = 10447 OR "PersonID" = 10403 OR "PersonID" = 10414; > Yes, but the real question is why is the query 4 times slower when > UseDeclareFetch is enabled (FETCH was set to 100)? > > I would have expected that the ODBC driver is fetching 100 rows in advance and > thus the query should execute in less than a second instead of 30 seconds. > > Rainer > > ---------------------------(end of broadcast)--------------------------- > TIP 2: Don't 'kill -9' the postmaster >
В списке pgsql-odbc по дате отправления
От: Mark Cave-Ayland
Дата: