Re: Why is UseDeclareFetch so slow?
От | David Gardner |
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Тема | Re: Why is UseDeclareFetch so slow? |
Дата | |
Msg-id | 46828A2E.6020201@gardnerit.net обсуждение исходный текст |
Ответ на | Re: Why is UseDeclareFetch so slow? (Rainer Bauer <usenet@munnin.com>) |
Список | pgsql-odbc |
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 >
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