joins are slow ?

[Ruslan Zasukhin]

On 9/25/04 11:21 AM, "olivier" <vidal_olivier at yahoo.fr> wrote:

Hi Oliver

> valentina 1.90
> RB 5.5.3
> 
> Hi Ruslan and list,
> 
> Join them between two tables are sometimes very slow. It is normal?

I think problem can be here:

Assume T1 have 10 records, but T2 million.

It is always good idea put smaller table on left in the join condition.

Valentina try do this self.
But I remember still some cases fails to do this.

So if you self as developer know info about size of database then try put it
on left side of join condition.


> I give you an example with a db of 378 000 records without join, and
> another db with the same data but consisted of two connected tables.
> The requests on both connected tables are fast if clauses (where...)
> are precise.
> But if it is not the case, the requests are very slow. What is not the
> case with the same db but without join.
> 
> It is normal? Or it is a defect of Valentina?

In fact developers say that joins in Valentina are very fast.
So you need to search for problem.


> Naturally, in a lot of case, we cannot take place of joins and the
> requests are very often precise. But it can be very boring in certain
> cases, I think. Especially that my example was a join with two very
> simple tables, but with one join complexes?

Next. What size of cache you use?
Make sure it is 10-20 MB.



-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
-------------------------------------------------------------
e-mail: ruslan at paradigmasoft.com
web: http://www.paradigmasoft.com

To subscribe to the Valentina mail list go to:
http://lists.macserve.net/mailman/listinfo/valentina
-------------------------------------------------------------