CREATE TABLE dept_emp
(emp_no
int(11) NOT NULL,dept_no
char(4) NOT NULL,from_date
date NOT NULL,to_date
date NOT NULL,
PRIMARY KEY (emp_no
,dept_no
));
解法:
select dept_no, group_concat( emp_no) as employees
from dept_emp group by dept_no;
group_concat
group_concat( [DISTINCT] 要连接的字段 [Order BY 排序字段 ASC/DESC] [Separator ‘分隔符’] ).
样例:select id, group_concat(price) from goods group by id;