ｍｙｓｑｌ的第三次课堂作业

-- 课堂作业
CREATE TABLE employee(
	id INT PRIMARY KEY AUTO_INCREMENT , -- 序号
	NAME VARCHAR(20) ,	-- 性别
	sex VARCHAR(10) , 	-- 性别
	age NUMERIC(3) ,	-- 年龄
	province VARCHAR(10) , 	-- 省份
	city VARCHAR(10) ,	-- 城市
	degree VARCHAR(10) 	 -- 学历
);
-- 插入信息
INSERT INTO employee VALUES (NULL,'张三','男','23','湖南','衡阳','本科');
INSERT INTO employee VALUES (NULL,'李四','男','18','河北','北京','博士');
INSERT INTO employee VALUES (NULL,'张兰','女','22','湖北','武汉','硕士');
INSERT INTO employee VALUES (NULL,'李健','男','24','湖南','长沙','本科');
INSERT INTO employee VALUES (NULL,'张晓','女','15','黑龙江','哈尔滨','高中');
INSERT INTO employee VALUES (NULL,'陈家','男','20','新疆','乌鲁木齐','初中');
INSERT INTO employee VALUES (NULL,'文星','男','25','浙江','杭州','本科');
INSERT INTO employee VALUES (NULL,'谷四','男','22','江西','景德镇','小学');
INSERT INTO employee VALUES (NULL,'谭颇','男','26','浙江','温州','高中');
INSERT INTO employee VALUES (NULL,'郑牛','男','24','广东','广州','硕士');
INSERT INTO employee VALUES (NULL,'尹茂','女','28','四川','宜宾','中专');
INSERT INTO employee VALUES (NULL,'冯先','男','25','台湾','高雄','博士');
INSERT INTO employee VALUES (NULL,'肖费','男','24','香港','旺角','本科');
INSERT INTO employee VALUES (NULL,'王麻子','女','22','湖南','邵阳','小学');
INSERT INTO employee VALUES (NULL,'颇星','女','25','辽林','沈阳','高中');
INSERT INTO employee VALUES (NULL,'吴剑','男','20','河北','石家庄','本科');
INSERT INTO employee VALUES (NULL,'张维','男','26','湖南','张家界','高中');
INSERT INTO employee VALUES (NULL,'张伟','男','21','江苏','苏州','高中');
-- 查看employee表
SELECT * FROM employee;

-- 各省份有多少人口？
SELECT COUNT(*) AS 个数,e.province FROM employee e  GROUP BY e.province;

-- 各省份学历分布人口
SELECT  e.province,e.degree ,e.city,COUNT(*) AS 学历个数  FROM employee e GROUP BY e.province,e.degree,e.city ;

-- 性别的分布
SELECT  e.province,e.sex,COUNT(*) AS 个数  FROM employee e GROUP BY e.sex,e.province;

-- 性别的学历的分布
SELECT e.sex,e.degree ,COUNT(*),e.province FROM  employee e GROUP BY e.sex,e.degree,e.province;