Question

我通过许多方法尝试了很多次，但是我无法解决这个问题...

我正在执行Oracle SQL查询：

SELECT
    TRUNC(months_between(sysdate, DateofBirth) / 12) AS "age"
FROM players
group by age
HAVING COUNT 
    (TRUNC(months_between(sysdate, DateofBirth) / 12)) > 30;

第4行出现错误： ORA-00904：“ AGE”：无效的标识符

有什么想法吗？

Answer 1

不要通过以下方式在您的群组中添加别名：

SELECT
    TRUNC(months_between(sysdate, DateofBirth) / 12) AS "age"
FROM players
group by
    TRUNC(months_between(sysdate, DateofBirth) / 12)
HAVING
    COUNT(TRUNC(months_between(sysdate, DateofBirth) / 12)) > 30;

Answer 2

在Oracle和SQL Server中，不能在GROUP BY中使用术语您在SELECT子句中定义的子句，因为GROUP BY是在SELECT子句之前执行。

https://stackoverflow.com/a/3841804/6358346

正确的方法：

SELECT TRUNC(months_between(sysdate, DateofBirth) / 12) AS "age"
FROM players
GROUP BY TRUNC(months_between(sysdate, DateofBirth) / 12)
HAVING COUNT(TRUNC(months_between(sysdate, DateofBirth) / 12)) > 30;

Group By子句中的别名-无效的标识符

2 个答案: