Re: [PERFORM] Performance bug in prepared statement binding in 9.2?

2013-11-13 Thread Tom Lane
Josh Berkus writes: >> What I'm hoping will happen next is that the complainants will hot-patch >> that and see if it fixes their problems. We can't really determine >> what to do without that information. > Unfortunately, the original reporter of this issue will not be available > for testing f

Re: [PERFORM] Performance bug in prepared statement binding in 9.2?

2013-11-13 Thread Josh Berkus
Tom, > There's an abbreviated version of this argument in the comments in > my proposed patch at > http://www.postgresql.org/message-id/11927.1384199...@sss.pgh.pa.us > What I'm hoping will happen next is that the complainants will hot-patch > that and see if it fixes their problems. We can't rea

Re: [PERFORM] Horrific time for getting 1 record from an index?

2013-11-13 Thread Merlin Moncure
On Tue, Nov 12, 2013 at 6:22 PM, Jim Nasby wrote: > On 11/12/13 6:17 PM, Jeff Janes wrote: >> >> I verified that this is the case--the empty pages remain linked in the >> tree until a vacuum removes them. But walking through empty leaf pages is >> way faster than resolving pages full of pointers

[PERFORM] CREATE TABLE AS WITH FREEZE ?

2013-11-13 Thread Marc Mamin
Hello, Does anything speaks again adding a "WITH FREEZE" option to "CREATE TABLE AS" , similar to the new COPY FREEZE feature ? best regards, Marc Mamin

Re: [PERFORM] BitMap Heap Scan & BitMap Index Scan

2013-11-13 Thread Torsten Förtsch
On 10/11/13 08:32, monalee_dba wrote: > I would like to know, What is BitMap Heap Scan & BitMap Index Scan? When > I use EXPLAIN for query, which has LEFT JOIN with 4 different table then > some time query planner uses Bitmap Heap Scan and some time Bitmap Index > Scan? Check out this great presen

Re: [PERFORM] Order By Clause, Slows Query Performance?

2013-11-13 Thread Albe Laurenz
monalee_dba wrote: > Eg. SELECT col1, col2, col3,col10 FROM table1; > > For above query If I didn't mention ORDER BY clause, then I want to know > selected data will appear in which order by a query planner? > > Because I have huge size table, and when I applied ORDER BY col1, col2..in > quer