[PERFORM] Perfomance of views

2005-10-26 Thread Svenne Krap
Hi there. I am currently building a system, where it would be nice to use multiple levels of views upon each other (it is a staticstics system, where traceability is important). Is there any significant performance reduction in say 10 levels of views instead of one giant, nested

Re: [PERFORM] Perfomance of views

2005-10-27 Thread Svenne Krap
: Svenne Krap wrote: Hi there. I am currently building a system, where it would be nice to use multiple levels of views upon each other (it is a staticstics system, where traceability is important). Is there any significant performance reduction in say 10 levels of views instead of one giant

Re: [PERFORM] Perfomance of views

2005-10-27 Thread Svenne Krap
Tom Lane wrote: There's been some discussion of inline-expanding SQL functions that return sets when they are called in FROM, which would make a SQL function that contains just a SELECT effectively equivalent to a view as far as the planner's powers of optimization go. No one's tried to make

[PERFORM] multi-layered view join performance oddities

2005-10-30 Thread Svenne Krap
Hi there. I have tried to implement the layered views as suggested earlier on one of the simplest queries (just to get a feel for it). And there seems to be something odd going on. Attached are all the statemens needed to see, how the database is made and the contents of postgresql.conf and

Re: [PERFORM] multi-layered view join performance oddities

2005-10-30 Thread Svenne Krap
hole question becomes, how do I get the planner to make a better estimation of the returned rows. I am not sure, I can follow your moving-the-union-all-further-out advice, as I see no different place for the unioning of the two datasets. Maybe one of the core devs know, where to fiddle :) Svenne S

Re: [PERFORM] multi-layered view join performance oddities

2005-10-30 Thread Svenne Krap
Tom Lane wrote: Svenne Krap [EMAIL PROTECTED] writes: create view ord_institutes_sum as SELECT ord_property_type_all.dataset_id, ord_property_type_all.nb_property_type_id, 0 AS institut, sum(ord_property_type_all.amount) AS amount FROM ord_property_type_all GROUP

Re: [PERFORM] Performance problems with multiple layers of functions

2006-03-24 Thread Svenne Krap
Tom Lane wrote: where (flow_direction, dataset_id) in (select * from new_func(122)) Is this form of multi-column IN mentioned anywhere in the docs? I can't find it. Svenne smime.p7s Description: S/MIME Cryptographic Signature