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List:       mysql-odbc
Subject:    Slow select * with MyODBC
From:       "Alain Charroux" <Alain.Charroux () kxen ! com>
Date:       2003-07-25 8:48:34
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We need to do a select on BIG table (1,000,000)
As I can see, by default MySQL browse all the table and put the resultset in client \
memory. The effect is that the memory usage dramatically increases and CPU is 100% \
for a LONG time BEFORE having the first row.

If found the magic switch -q (don't cache result) wich is working fine for the mysql \
frontal : no memory usage, reasonable CPU and the first line arrives immediately

When I apply the same switch to MyODBC driver (windows version) it is half working : \
the memory usage is OK meaning that the result set is not transferred in memory. But \
the CPU is still 100% for a long time before we have the first row coming !!! I have \
several other options with MyODBC , no impact. Pbp is that we must use MyODBC Any \
idea ? Is this a pbm with Windows version of MyODBC, of all versions.
Is there another magic switch somewhere ?
Is there some options to programatically apply on the ODBC Connection handle, or \
statement handle ?

Thx

Alain Charroux 
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