Re: [HACKERS] [Devel 9.2] Index-only scan in count aggregation

2012-04-18 Thread Robert Haas
On Wed, Apr 18, 2012 at 12:52 PM, Robert Haas wrote: > On Wed, Apr 18, 2012 at 12:40 PM, Emanuel Calvo > wrote: >>> I'm not sure what you're unhappy about.  It seems that the query >>> planner picked the fastest plan (a sequential scan) and then when you >>> disabled that it picked the second-fa

Re: [HACKERS] [Devel 9.2] Index-only scan in count aggregation

2012-04-18 Thread Robert Haas
On Wed, Apr 18, 2012 at 12:40 PM, Emanuel Calvo wrote: >> I'm not sure what you're unhappy about.  It seems that the query >> planner picked the fastest plan (a sequential scan) and then when you >> disabled that it picked the second-fastest plan (an index-only scan). >> >> The index-only scan wou

Re: [HACKERS] [Devel 9.2] Index-only scan in count aggregation

2012-04-18 Thread Emanuel Calvo
El día 18 de abril de 2012 18:17, Robert Haas escribió: > On Wed, Apr 18, 2012 at 12:13 PM, Emanuel Calvo > wrote: >> Hi guys, >> >> I'm one of the nightly sources of 9.2devel. I was trying some simple >> queries and I realized something: >> >> stuff=# explain (analyze true, costs true, buffers

Re: [HACKERS] [Devel 9.2] Index-only scan in count aggregation

2012-04-18 Thread Robert Haas
On Wed, Apr 18, 2012 at 12:13 PM, Emanuel Calvo wrote: > Hi guys, > > I'm one of the nightly sources of 9.2devel. I was trying some simple > queries and I realized something: > > stuff=# explain (analyze true, costs true, buffers true, timing true, > verbose true) select count(i) from lot_of_value

[HACKERS] [Devel 9.2] Index-only scan in count aggregation

2012-04-18 Thread Emanuel Calvo
Hi guys, I'm one of the nightly sources of 9.2devel. I was trying some simple queries and I realized something: stuff=# explain (analyze true, costs true, buffers true, timing true, verbose true) select count(i) from lot_of_values; Q