Hello Tom, Monday, January 14, 2019, 6:15:31 PM, you wrote:
> =?utf-8?q?PG_Doc_comments_form?= <nore...@postgresql.org> writes: >> https://www.postgresql.org/docs/current/queries-table-expressions.html#QUERIES-LATERAL >>> The resulting row(s) are joined as usual with the rows they were computed >>> from. >> Here is not so clear what 'joined as usual' mean. > Why not? Advanced users may understand that, but from my beginner point of view this is not. I do not understand that sentence until read whole text and about LEFT JOIN LATERAL. Even now 'usual' may mean: CROSS/RIGHT/FULL?? >> Probably DOC should explicitly say that if LATERAL function return empty set >> then current row is excluded from result set > That would be wrong for "LEFT JOIN LATERAL ...", so it does not seem > like an improvement. LATERAL != LEFT JOIN LATERAL it would be more clear if DOC will be more explicit. > regards, tom lane -- Best regards, Eugen Konkov
