Re: Views of views, complexity and speed.

El martes 05 de febrero, Jan Wieck escribió:
> bombadil@wanadoo.es wrote:
> >  In order to avoid complexity, some views looks in other views and
> >  join them for getting data.
> >
> >  I see queries against that views result slower than queries against
> >  plane tables or simple views by an order of magnitude (when not two).
> >
> >  My question is: if I would make complex views looking in plain tables
> >  instead of other views, could I gain speed with the cost of more
> >  difficult maintainability and readability?
> >
> >  Sorry for lazy data and arguments. If any of you think that detailed
> >  tables and views may help, i can send them without problem.
>
>     Asking  for  qualified  opinions and comments "only" and then
>     beeing lazy on data and arguments, tztztz ... man!

 Emmmmm, sorry 0:)

>     The question I have is what do you really compare?  You  said
>     "looking  in  plain tables instead of other views". Does that
>     mean your query is faster when you build one big view against
>     all  the base tables instead of cascaded views, or what? What
>     is the performance difference if you  instead  of  using  the
>     cascaded  views  query  all  the  base  tables  in a big join
>     directly?

 Your comment resumes very well my essential question. I only want to
 know if there is a reason for thinkink that a cascade of views can be
 slower than a complex view that includes all tables. Is the planner
 well tuned for working with this complex cases (cascade of views)?

 Actually I am making experiments with all this stuff. Better idea
 than sending a lazy question in the list.

 Sorry again, and thanks for interest.

 Greets.

                             David