mysql - 每个派生表必须有自己的别名 mysql 数据库

Question

我正在 MySQL 上运行此查询，但出现以下错误:

每个派生表必须有自己的别名。

SELECT MAX (mycount) FROM 
(SELECT CreatedBy,COUNT(CreatedBy) mycount 
FROM audit_csp_evaluation 
GROUP BY CreatedBy);

Answer 1

您必须命名派生表，如下所示:

SELECT MAX(x.mycount) AS max_mycount
FROM 
(
 SELECT CreatedBy
    , COUNT(CreatedBy) AS mycount 
FROM audit_csp_evaluation 
GROUP BY CreatedBy
) x;

x 是我为派生表指定的名称。