从titles表获取按照title进行分组
从titles表获取按照title进行分组
http://www.nowcoder.com/questionTerminal/72ca694734294dc78f513e147da7821e
从titles表获取按照title进行分组,每组个数大于等于2,给出title以及对应的数目t。
CREATE TABLE IF NOT EXISTS "titles" (emp_no int(11) NOT NULL,title varchar(50) NOT NULL,from_date date NOT NULL,to_date date DEFAULT NULL);
思路:采用Group by+Having
select title,count(emp_no) as t from titles group by title having t>=2;
