报错 ORA-00937: 非单组分组函数
SELECT DW AS 单位,XB AS 性别,SUM(COUNT) AS 人数 FROM stu_table;

加了SUM(COUNT) AS 人数就报错. 请教~

[解决办法]
SELECT DW AS 单位,XB AS 性别,SUM(COUNT) AS 人数 FROM stu_table
group by dw xb;