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From:Christian Mack Date:September 13 1999 7:14pm
Subject:Re: Speed with Access97
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Didier wrote:
> 
> hi!
> 
> recently I've exported tables of an access db to mysql on a linux
> machine. for the users I kept access as gui. the tables are linked
> via odbc.
> 
> unfortunately queries are extremely slow.
> one particular query now suddenly takes more than 4 minutes to display
> 23 rows.
> 
> When writing the same SQL-Query by hand and submitting it to the server
> on the linux machine via telnet the query takes 0.2 s and another 2s
> to display.
> 
> I've now used the same SQL in an Access Pass-Through query. Everything
> is now wonderfully fast.
> Unfortunately when doing Pass-Through queries the resulting set is read-only.
> furthermore Pass-Through queries seem not to support parameters from
> forms.
> select * from users where uid=[Forms]![F_ShowUser]![UserID];
> 
> How come that queries going through access and myodbc are so much
> slower?
> I am new to MySQL and SQL, so maybe I'm missing the obvious.
> 
> Thanks for your help
>  Didier

Hi Didier

Access does some processing on the given SQL query.
So it often doesn't send what you expect it to send to mysql.
To see the actual SQL send by Access you can turn on logging in MyODBC.

The Pass-Through query prevents this processing.
In this processing step the form parameters are substituted, so you can't use them with
Pass-Through.

Tschau
Christian

Thread
Speed with Access97Didier12 Sep
  • Re: Speed with Access97Christian Mack13 Sep
  • Re: Speed with Access97Colin McKinnon14 Sep