-----Ursprüngliche Nachricht----- Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im Auftrag von Fredrik Larsen Gesendet: Donnerstag, 19. September 2019 17:29 An: SQLite mailing list <sqlite-users@mailinglists.sqlite.org> Betreff: Re: [sqlite] [EXTERNAL] Group-by and order-by-desc does not work as expected ... Hick; ORDER BY x DESC >is< covered by index. Btree-indexes allows traversal both ways. You can see this if you remove GROUP_BY. ...
True and nothing new, but not the point. After doing GROUP BY x over the covering index, the result rows would be returned by x ASC. There is no index on the rowset returned by the GROUP BY, as the rows only exist one at a time. Therefore, the only way to get them into ORDER BY X DESC is to sort them. Gunter ___________________________________________ 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
