Re: How can i monitor exactly what (partition) tables are accessed by a query?

Jov
blog: http:amutu.com/blog <http://amutu.com/blog>

2014-09-19 2:44 GMT+08:00 Robert Nix <robert(at)urban4m(dot)com>:

> I'm experiencing a problem with queries apparently not using the check
> constraints of my partition tables (tried constraint_exclusion =partition
> and =on with same results) and explain isn't sufficient to diagnose the
> issue because the value for the check constraint in the query comes from a
> join condition.
>
> What i need is a way to see exactly what tables are actually accessed by
> the query.
>
> When i hardcode the check constraint column's value into the query, the
> explain plan reports what i expect it should be executing but the
> performance of the query indicates that the partitions are not actually
> being used when the check constraint value is obtained from a join
> condition.
>
How did you find the partitions are not actually being used?
You can try to use explain analyze to see the acutally running paln.

>
> Any and all help appreciated.
> --
> .nix
>