其實這么寫理論上是對的，很多博客教程都是這樣子寫的。。 select * from (SELECT * FROM article WHERE is_top=0 ORDER BY id DESC) as t1unionselect * from (SELECT * FROM article WHERE is_top=1 ORDER BY start_time desc) as t2
然后還是發現子查詢的排序無效，尷尬，后來才發現如果order by 不帶limit，會被優化器干掉，導致語句就是： select * from (SELECT * FROM article WHERE is_top=0 ) as t1unionselect * from (SELECT * FROM article WHERE is_top=1) as t2
解決方案： select * from (SELECT * FROM article WHERE is_top=0 ORDER BY id DESC limit 999999) as t1unionselect * from (SELECT * FROM article WHERE is_top=1 ORDER BY start_time desc limit 999999) as t2

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