Hi David - On Fri, Mar 16, 2018 at 4:40 PM, David G. Johnston < david.g.johns...@gmail.com> wrote:
> First reaction is to ARRAY_AGG(DISTINCT x) and then write a function that > converts that array into a string by extracting 'letter' from each cell in > the array. > > Thinking it over a bit you have two columns that both are aggregates but > that are otherwise independent of each other. Since they are independent > they cannot be aggregated at the same time. You need to write a two > subqueries, either in the target list or as separate from/join items, and > then join the already aggregated queries together on their common group by > column. > > The presence of DISTINCT here (and, IMO, generally), even if it worked, > would be an indicator that something is not quite right. > > thank you for confirming my feeling that DISTINCT is a bad indicator here... But you say that "tiles" and "word (score)" are unrelated and this does not seem true to me: For each move id aka "mid" there is a JSON value, describing how the player played the letter tiles. And for the same "mid" there is a list of one or more "word (score)"s achieved... Maybe it is possible to GROUP BY tiles somehow or some kind of special SQL JOIN? Regards Alex
