"He Shiming" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] >> select NAME, group_concat(COUNT), group_concat(TYPE) >> from ( >> select T1.NAME NAME, T2.COUNT COUNT, T2.TYPE TYPE >> from T1 left join T2 on T1.ID=T2.REFID >> order by T2.COUNT); >> > Thanks for the hint. It works, but I noticed the query takes much > longer to complete (5 times actually in my smaller testing db).
Sorting is not free. > Can it be done without a sub-select? I can't think of a way. > About performance, it is important in my scenario. Isn't it always? > That's why I used > group_concat. I don't quite see how this conclusion follows from premises. > I could use additional queries to fetch the data from > T2. But I figured as long as it's done in a single query instead of > multiple, the performance shall be better. Please correct me if I'm > wrong here, because I'm not so sure if I'm heading in the right > direction. I don't understand what exactly you are trying to achive. In any case, when in doubt, try it both ways and see which one performs better. Igor Tandetnik _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
