Re: bad performance for Access, ODBC and Postgres

On Thu, 29 Jul 2004 14:57:25 +0200, Eric HAGENBACH
<eric.hagenbach@xxxxxxxxx> wrote:
> Jean-Max Reymond a écrit :
> 
> >Hi,
> >I have very poor access whith a front end Access 2003, ODBC and Postgres 
> >7.4.3.
> >Much time to find a record in a table ff 13000 records with indexs.
> >Sniffing the network, I can see a lot of traffic and the CPU of
> >postmaster is about 30% (P4, 2.8 GHz). It seems that all the data's
> >are backed on the client side and then, analyzed.
> >Does it exist an option to improve the performances ?
> >thanks,
> >
> >
> >
> Maybe you can use the EXPLAIN command to see what query plan the system
> creates for your query (you can see the where condition,  which index is
> used, ...)
> 
> Eric.
> 

EXPLAIN is for identified requests and I don't know which request Access sends.
It seems that Access open a cursor on the database and reads each
record one by one and tries to match with the condition. This is the
only way  I can explain such behaviour and it is of course very silly.

-- 
Jean-Max Reymond
CKR Solutions
http://www.ckr-solutions.com

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TIP 9: the planner will ignore your desire to choose an index scan if your
      joining column's datatypes do not match