mysql合并两个表并排序结果

Question

请原谅我的无知。 我想对表invcount2和reserve1进行合并。 下面的代码有什么错误？

mysql_query("select distinct Name from exam1sem.invcount2  WHERE Name not in 
(select  Name from exam1sem.invcount2 where Date='$date' AND Time='$time'
 union select  Name from exam1sem.reserve1 where Date='$date' AND 
Time='$time') 

union

select distinct Name from exam1sem.reserve1 WHERE Name not in (select  Name 
from exam1sem.invcount2 where Date='$date' AND Time='$time'
union select  Name from exam1sem.reserve1 where Date='$date' AND 
Time='$time'
)  

order by Avail, TD, NOD
");

Answer 1

看来，当您使用distinct关键字时，您无法按select语句中不存在的内容进行order by 。

您可以检查此SQL链接