Question

我试过了：

    SELECT ProductId AS GmId, (
    SELECT SUM(Amount) FROM tmp WHERE ProductId=GmId AND (AssignDate BETWEEN '$Date1' AND '$Date2')
) AS sum0, (
    SELECT SUM(Amount) FROM tmp WHERE ProductId=GmId AND (AssignDate BETWEEN '$Date2' AND '$Date3')
) AS sum1 FROM (
    SELECT * FROM somerealtable
) tmp GROUP BY ProductId

但mysql显示错误消息table <database name>.tmp doesn't exist!

如何使这项工作？

编辑：sqlfiddle示例here

EDIT2：更复杂的sqlfiddle sample。

Answer 1

无需使用子查询。您可以使用 JOIN

执行相同的操作

试试这个：

SELECT a.ProductId AS GmId, 
       SUM(IF(b.AssignDate BETWEEN '$Date1' AND '$Date2', b.Amount, 0)) AS sum0, 
       SUM(IF(b.AssignDate BETWEEN '$Date2' AND '$Date3', b.Amount, 0)) AS sum1
FROM somerealtable a
LEFT JOIN tmp b ON a.ProductId=b.GmId 
GROUP BY ProductId

mysql如何访问子查询在另一个子查询中生成的临时表？

1 个答案: