I already asked this question without an answer, but as it hidden somewhere nested deeply in another thread I think it may have simply gone under the radar. Apologies for the duplication if you already saw it!
How is the behaviour of (custom) window functions defined? Specifically, in the presence of an ORDER BY on the window. The functionality of row_number/rank/dense_rank seems to require that xStep and xInverse are called on rows in the order specified by ORDER BY. And, indeed, the implementation of row_number() in the sqlite source seems to rely on being called in the same order as ORDER BY, but at the same time the documentation states: "the built-in window functions, however, require special-case handling in the query planner and hence new window functions that exhibit the exceptional properties found in the built-in window functions cannot be added by the application." So does this indeed mean that these builtin ones are handled specially and other windows functions have to accept/deal with having their window arguments added/removed in an arbitrary order? Kind regards, Merijn _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
