hyelluas <helen_yelluas@mcafee.com> writes:
> sorry, my table has many columns and missed the datex when make it look
> smaller.
> datex is the column in the table. This is the driving constraint.
> My task is to have 30 days of data with 5mln to 10 mln rec in 1 hour table,
> so I partition it by hour table and combine them into days, which are
> combined into month total table. My query will have " where datex between a
> and b" , for 2-5 days ,across the "day" boundaries , so that partition
> exclusion is so much important.
> I don't undertsand why the optimizer goes to the children when it hits the
> constraint on the parent that shows the date range on that parent ?
Well, you've been very careful to hide all the information that might
let anyone explain it. Possibly relevant information here includes the
datatype of the datex column, the Postgres version you're running, and
what you've got the constraint_exclusion parameter set to.
regards, tom lane