Select distinct(LAC_CI) from (Select LAC_CI from `dtdb_sh_test`.dt_measurment where callid='04021002ms31310379260576' union Select LAC_CI from `dtdb_sh_test`.dt_measurment where callid='04021002ms31310379260576')

在执行稍微复杂查询的时候，

MySQL有时会遇到如下报错情况：

Error Code : 1248
Every derived table must have its own alias

 

解决方法：

在执行复杂查询处为你的表任意起个别名就可以了。

Select distinct(LAC_CI) from (Select LAC_CI from `dtdb_sh_test`.dt_measurment t where t.callid='04021002ms31310379260576' union Select LAC_CI from `dtdb_sh_test`.dt_measurment  d where d.callid='04021002ms31310379260576') as t

此处 as  t  虽然无任何作用和意义，但是SQL语句是万万少不得的。