how to change the index chosen in plan?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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. So I re-wrote the query as below: select a.* from a where a.aid in (select aid from b where bid=8) and a.col1=33 a.col2=44 But surprisingly, postgresql didn't change the plan. it still chose to index scan on a.col1. How can I re-wirte the query so postgresql will scan on b.bid first?

--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance


[Postgresql General]     [Postgresql PHP]     [PHP Users]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Yosemite]

  Powered by Linux