On 06-01-2015 PM 04:00, Ashutosh Bapat wrote: > On Tue, Jan 6, 2015 at 12:23 PM, Atri Sharma <atri.jiit@gmail.com> wrote: >>> We can eliminate the new node and put onus or having the right order on >>> the user like we do with volatile setting of the function. >>> >>> >> >> That is exactly what the new node does, since we are not re sorting right >> now in case the order is wrong. Please see my explanation upthread, >> OrderCheck node's primary purpose is to check for a user error in the >> result rows order. The onus right now to give correct order is on user. >> >> > Even checking whether the output of the function is in the right order or > not, has its cost. I am suggesting that we can eliminate this cost as well. > For example, PostgreSQL does not check whether a function is really > immutable or not. >
Sounds something like ORDERED BY x implying output is "known" ordered by x perhaps enough hint for the planner to make necessary plan choices though I may be wrong.
I may be missing something, but isnt what you mentioned the exact functionality this patch adds?
