Re: joins and performances : general question

You sent this to a bunch of db newsgroups. What dbms are you running? If it's a good one, nine times out of ten, the optimizer will do a better job of figuring out a good query plan than you will (assuming your stats are up to date).

Rick Gebethner

Christian Bruno wrote:

> hello,
> it is a very general question :
>
> i have to write sql queries using lot of Joins (mainly left outer and inner
> joins)
>
> is there rule(s) to apply to write these sql orders, having knowledge of the
> average number of rows in my tables ? for example : which order to use for
> joins in a particular query ? is it better to begin or to end with the join
> that retrieves the more rows in the database ? it is better to use INNER
> joins than LEFT OUTER JOINS ?
>
> thanks for any comments or ideas !
> Regards,
> Christian
Received on Wed Nov 24 1999 - 14:52:19 CST