Re: Views of views, complexity and speed.

bombadil@wanadoo.es wrote:
>  Hello list.
>
>  I have a question about complexity of queries and performance. I only
>  look for qualified opinions and comments.
>
>  In my database I have a pool of tables and views with rules for
>  inserting, updating and deleting.
>
>  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!

    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?


Jan

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