Re: [ODBC] Why is UseDeclareFetch so slow?

From: Hiroshi Inoue <inoue(at)tpf.co.jp>
Date: Wed Jun 27 2007 - 10:46:20 EDT

Rainer Bauer wrote:
> Hello Hiroshi,
>

>>> So my questions are
>>> 1) Is there any chance the driver itself could be enhanced like Dimitri
>>> suggested here:
>>> <
http://archives.postgresql.org/pgsql-performance/2007-06/msg00512.php>?
>> You can specify the fetch count in UseDeclareFetch mode using the
>>  Cache Size option or FETCH=N connection string.

>
> 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.

Could you send me directly the Mylog output ?

regards,
HIroshi Inoue

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               http://archives.postgresql.org Received on Wed Jun 27 10:47:56 2007