mysql - 如何在稍微复杂的mysql查询上按顺序分组

(SELECT dtable.*, new_apps.top as t1 FROM app_detailsvvv as dtable INNER JOIN new_apps ON
new_apps.trackId=dtable.trackId WHERE (SELECT COUNT(*) AS c FROM compositions as dtablev
WHERE parent='169469' AND trackId=dtable.trackId AND new_apps.top > 0)>0) UNION
(SELECT *, 301 FROM app_detailsvvv as dtable WHERE (SELECT COUNT(*) AS c FROM compositions
as dtablev WHERE parent='169469' AND trackId=dtable.trackId)>0) ORDER BY t1 ASC, trackName
ASC LIMIT 0,12

这个查询给我带来了重复，我怎么可以通过trackId分组？

最佳答案

将trackid作为SELECT语句的一部分...

SELECT new_apps.trackId,
       ..etc...
..
..

GROUP BY 1

确保其余的SELECT项（包括子SQL查询）已经聚合-例如MAX，FIRST，SUM或将它们分组为单个结果的内容。