14 Oct 2006 00:59
Re: [PERFORM] Hints proposal
Josh Berkus <josh <at> agliodbs.com>
2006-10-13 22:59:17 GMT
2006-10-13 22:59:17 GMT
Andreas, > I think we need to more precisely define the problems of our system with > point in time statistics > > -- no reaction to degree of other concurrent activity > -- no way to react to abnormal skew that only persists for a very short > duration > -- too late reaction to changing distribution (e.g. current date column > when a new year starts) > and the variant: too late adaption when a table is beeing filled > -- missing cost/selectivity estimates for several parts of the system How would we manage point-in-time statistics? How would we collect them & store them? I think this is an interesting idea, but very, very hard to do ... -- -- --Josh Josh Berkus PostgreSQL <at> Sun San Francisco ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
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