Ankit Kumar Pandey <itsankitkp@gmail.com> writes:
> Question is: Average of id for partition name (A) should be 6/4 = 1.5
> for all rows in that partition but this result is seen only at the last
> one row in partition (A). Am I missing here something?
https://www.postgresql.org/docs/current/tutorial-window.html
particularly:
By default, if ORDER BY is supplied then the frame consists of all
rows from the start of the partition up through the current row, plus
any following rows that are equal to the current row according to the
ORDER BY clause.
regards, tom lane