mysql中date连接time

SELECT *,CONCAT(a1.Date," ",a1.Time) as w FROM a as a1 , b as b1 where CONCAT(a1.Date," ",a1.Time)>CONCAT(b1.Date," ",b1.Time) 这样么 应该可以不用时间戳比较

用union拼接一下就行了，形如

selet * from tablename where hdtime>='2013-5-6' order by hdtime

union all

selet * from tablename where hdtime<'2013-5-6' order by hdtime desc

当然这不是标准的语法，mysql中的时间比较偶不太清楚，你要自己修改一下。

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