Re: [PERFORM] Understanding explains

2004-10-11 Thread Francisco Reyes
On Mon, 11 Oct 2004, Rosser Schwarz wrote: In general, it's best to let the planner make the appropriate choice without any artificial constraints. As someone suggested ran with Explain analyze. With seqscan_off was better. Ran a vacuum analyze this afternoon so the stats were up to date. Although

Re: [PERFORM] Understanding explains

2004-10-11 Thread Rosser Schwarz
while you weren't looking, Francisco Reyes wrote: > Is there any disadvantage of having the enable_seqscan off? Plenty. The planner will choose whichever plan looks "cheapest", based on the information it has available (table size, statistics, &c). If a sequential scan looks cheaper, and in you

[PERFORM] Understanding explains

2004-10-11 Thread Francisco Reyes
Is there a tutorial or reference to the different terms that appear on the explain output? Items such as "Nested Loop", "Hash".. Also is there a way to easily tell which of two explains is "worse". Example I am running a query with "set enable_seqscan to off;" and i see the explain now shows in