Re: how to change the index chosen in plan?

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No, it's not the analyze problem. For some other values on b.bid such as 9, 10, the plan is fine since there a a lot of rows in table b for them. But for some specific values such as 8 I want the plan changed.

于2012年6月8日 22:10:58,Tom Lane写到:
Rural Hunter <ruralhunter@xxxxxxxxx> writes:
I have a query like this:
select a.* from a inner join b on a.aid=b.aid where a.col1=33 a.col2=44
and b.bid=8
postgresql selected the index on a.col1 then selected the index on
b.bid. But in my situation, I know that the query will be faster if it
chose the index on b.bid first since there are only a few rows with
value 8.

If you know that and the planner doesn't, maybe ANALYZE is called for.

			regards, tom lane




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