Re: [PERFORM] Multiple index builds on same table - in one sweep?

2011-04-10 Thread Scott Marlowe
On Sun, Apr 10, 2011 at 8:29 PM, Greg Smith wrote: > On 04/09/2011 01:23 PM, Chris Ruprecht wrote: >> >> Maybe, in a future release, somebody will develop something that can >> create indexes as inactive and have a build tool build and activate them at >> the same time. Food for thought? >> > > We

Re: [PERFORM] optimizer parameters

2011-04-10 Thread Greg Smith
On 04/10/2011 07:27 PM, Tomas Vondra wrote: But if you need more details, then I quess the best approach to get it is to read the sources (search for the cost estimation etc.). There's a small fully worked out example of this in my book too, where I duplicate the optimizer's EXPLAIN cost c

Re: [PERFORM] Multiple index builds on same table - in one sweep?

2011-04-10 Thread Greg Smith
On 04/09/2011 01:23 PM, Chris Ruprecht wrote: Maybe, in a future release, somebody will develop something that can create indexes as inactive and have a build tool build and activate them at the same time. Food for thought? Well, the most common case where this sort of thing happens is wh

Re: [PERFORM] optimizer parameters

2011-04-10 Thread Tomas Vondra
There's a quite nice description in the docs: http://www.postgresql.org/docs/9.0/interactive/row-estimation-examples.html and a some more details for indexes: http://www.postgresql.org/docs/9.0/interactive/index-cost-estimation.html A bit more info about how this is used is available in this pr

[PERFORM] optimizer parameters

2011-04-10 Thread Radhya sahal
Dear ,all i would to ask you about how postgresql optimizer parameters :- 1- random page cost 2- cpu tuple cost3- cpu operator cost4- cpu index tuple cost5- effective cache size play as parameters in cost estimator equation  i imagine that cost function is the same as f(x,y,z,)=ax+by.. c