Replace LEFT with CROSS in all cases that you used LEFT as a hint. Not at all complex, apart from you having to discern between "hint" and "necessities".
-----Ursprüngliche Nachricht----- Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im Auftrag von Eric Grange Gesendet: Freitag, 23. März 2018 09:07 An: SQLite mailing list <sqlite-users@mailinglists.sqlite.org> Betreff: [EXTERNAL] Re: [sqlite] The upcoming 3.23.0 release > Add the LEFT JOIN strength reduction optimization that converts a LEFT JOIN into an ordinary JOIN A question on this one: I have been using LEFT JOIN for many years (and not juste in SQLIte) in cases where a JOIN could have been used as a way to "hint" query optimizers which tables to scan first, typically in cases where the WHERE is too complex or misleading for the optimizer (ie. whenever index statistics paint a wrong picture, for whatever specific reasons). I can see that change "breaking" optimized queries back to their original performance. Is there a planned "QUERY PLAN" or lightweight hinting is in the works? The current suggestions in the doc are to use cross joins or stat3/stat4 tables, but both are quite more complex to maintain, while just introducing a "LEFT" before a "JOIN" in a particular query used to be enough :) On Fri, Mar 23, 2018 at 1:06 AM, Olivier Mascia <o...@integral.be> wrote: ___________________________________________ Gunter Hick | Software Engineer | Scientific Games International GmbH | Klitschgasse 2-4, A-1130 Vienna | FN 157284 a, HG Wien, DVR: 0430013 | (O) +43 1 80100 - 0 May be privileged. May be confidential. Please delete if not the addressee. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
