I meant: SELECT title FROM tracks WHERE title >= :last_title AND (title>:last_title OR id>:last_id) AND title LIKE %Mad% ORDER BY title,id; better than SELECT title FROM tracks WHERE title LIKE %Mad% AND title >= :last_title AND (title>:last_title OR id>:last_id) ORDER BY title,id;
? Furthermore can the index improve select performance in both previous cases? Igor Tandetnik ha scritto: > "Andrea Galeazzi" <[email protected]> wrote in > message news:[email protected] > >> Is the order of WHERE clauses important as C-language is? >> > > No. The optimizer may, and often does, reorder the conditions in the > WHERE clause. > > >> For instance is >> >> SELECT title FROM tracks >> WHERE title ((title=:last_title AND id>:last_id) AND LIKE %Mad% >> >> better than >> >> SELECT title FROM tracks >> WHERE title LIKE %Mad% AND ((title=:last_title AND id>:last_id) >> >> ? >> > > Neither is better than the other: both are invalid and will produce a > syntax error. > > >> Anyway, can the index improve select performance in both previous >> cases? >> > > No. These statements won't actually run, and are thus beyond help. > > Igor Tandetnik > > > > _______________________________________________ > sqlite-users mailing list > [email protected] > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > __________ NOD32 3941 (20090317) Information __________ > > This message was checked by NOD32 antivirus system. > http://www.eset.com > > > > _______________________________________________ sqlite-users mailing list [email protected] http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
