MySQL中的子查詢WHERE子句使用

Question

我不是一個sql guru，但爲什麼這個查詢返回錯誤？

SELECT username FROM history as h 
    WHERE username IS NOT NULL AND updated>1342555201 AND updated<1342641599 
    AND WHERE (SELECT status FROM managers WHERE username=h.username) > 0 

如何在一個查詢中使用包含狀態的第二個表上的子查詢將狀態> 0的用戶名分組？

Answer 1

嘗試

SELECT h.username FROM history h 
INNER JOIN status s USING(username) 
WHERE h.updated BETWEEN 1342555201 AND 1342641599 
GROUP BY h.username 
HAVING s.status > 0 

注：

• INNER JOIN永遠retrive NOT NULL和用戶名的共同價值

• 我假定這兩個表具有相同的列名 .if bot^h的表有不同的列名，然後更改

  USING(username)與ON h.column_name = s.column_name

Answer 2

你不應該有2 WHERE語句

編輯：

也 - 你應該加入的經理表

Answer 3

你有一個where太多。

SELECT username FROM history as h 
WHERE username IS NOT NULL AND updated>1342555201 AND updated<1342641599 
AND WHERE (SELECT status FROM managers WHERE username=h.username) > 0 
    ^^^^^