Ken Tanzer <ken.tanzer@xxxxxxxxx> writes: >> => select f.id, f.f1,f.f2,array_agg(t.key2) from foo as f, >> jsonb_to_recordset(js) as t(key2 text) group by f.id; > After a little more thought and experimenting, I'm not so sure about this > part. In particular, I'm not clear why Postgres isn't complaining about > the f1 and f2 fields. (It's not giving the "must appear in the GROUP BY > clause or be used in an aggregate function" error that I would expect, and > that I am getting when I try to apply this to my real query.) > Can anyone explain to me why those fields don't need to be grouped? Thanks. If foo.id is a primary key, it knows that the "group by" doesn't really merge any rows of foo, so it lets you get away with that. I think this is actually required by spec, but am too lazy to go check right now. If foo.id isn't a primary key, then I'm confused too. Can we see the full declaration of the table? regards, tom lane
