On Tue, Feb 16, 2021 at 10:13 AM Michael Lewis <mle...@entrata.com> wrote:
> Sort Method: external >> merge Disk: 30760kB >> Worker 0: Sort >> Method: external merge Disk: 30760kB >> Worker 1: Sort >> Method: external merge Disk: 30760kB >> > > If you can increase work_mem, even setting it temporarily higher for the > session or transaction, that may dramatically change the plan. > I will try increasing work_mem for the session later today. > The advice given by Justin particularly about row estimates would be wise > to pursue. > > I'd wonder how selective that condition of score_name = > 'student_performance_index' is in filtering out many of the 9.3 million > tuples in that table and if an index with that as the leading column, or > just an index on that column would be helpful. > There are 1,206,355 rows where score_name='student_performance_idex'. > You'd need to look at pg_stats for the table and see how many distinct > values, and if student_performance_index is relatively high or low (or not > present) in the MCVs list. > I will look into that. > I am not sure if your query does what you want it to do as I admit I > didn't follow your explanation of the desired behavior. My hunch is that > you want to make use of a window function and get rid of one of the CTEs. > If you could tell me what part(s) are unclear I would appreciate it so that I can write a better comment. Thank you sooo much for all the feedback. It is *greatly* appreciated! Sincerely, Dane
