创建视图v_emp_dept_id_1，查询销售部门的员工姓名和家庭住址

CREATE VIEW v_emp_dept_id_1 AS

SELECT e.emp_name,e.address FROM dept d, emp e WHERE e.dept_id = 
(SELECT dept_id FROM dept WHERE dept_name = '销售部');

SELECT * FROM v_emp_dept_id_1;

创建视图v_emp_dept，查询销售部门员工姓名和家庭住址及部门名称。

CREATE VIEW v_emp_dept AS
SELECT e.emp_name,e.address,d.dept_name FROM dept d, emp e WHERE e.dept_id = 
(SELECT dept_id FROM dept WHERE dept_name = '销售部');

SELECT * FROM v_emp_dept;

创建视图v_dept_emp_count(dept_name,emp_count,avg_salay)，统计每个部门人数并计算平均工资。

CREATE VIEW v_dept_emp_count(dept_name,emp_count,avg_salay) AS
SELECT d.dept_name,a.emp_count,a.avg_salay FROM dept d,
(SELECT dept_id,COUNT(1) AS emp_count,AVG(salary) AS avg_salay FROM emp GROUP BY dept_id) a
WHERE d.dept_id = a.dept_id;

SELECT * FROM v_dept_emp_count;

修改视图v_emp_dept，查询销售部门员工姓名、家庭住址、工资和部门名称。

  ALTER VIEW v_emp_dept AS 
  SELECT e.emp_name,e.address,e.salary,d.dept_name FROM dept d, emp e 
  WHERE e.dept_id = 
(SELECT dept_id FROM dept WHERE dept_name = '销售部');

  SELECT * FROM v_emp_dept;

查看视图名称；
查看视图结构；
   

DESC v_emp_dept;
    查看创建视图语句；
 

  SHOW TABLE STATUS LIKE 'v_emp_dept';

删除以上三个视图。

DROP VIEW v_emp_dept;
DROP VIEW v_emp_dept_id_1;
DROP VIEW v_dept_emp_count;

SELECT * FROM emp;
SELECT * FROM dept;

创建一个提取emp表所有员工工资和的存储过程s1

DELIMITER $$

CREATE
    /*[DEFINER = { user | CURRENT_USER }]*/
    PROCEDURE `db_view`.`s1`()
    /*LANGUAGE SQL
    | [NOT] DETERMINISTIC
    | { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA }
    | SQL SECURITY { DEFINER | INVOKER }
    | COMMENT 'string'*/
    BEGIN
    SELECT SUM(salary) FROM emp;

    END$$

DELIMITER ;

调用存储过程s1
CALL s1();

创建存储过程s2，实现输入员工姓名后返回员工的家庭住址。

DELIMITER $$

CREATE
    /*[DEFINER = { user | CURRENT_USER }]*/
    PROCEDURE `db_view`.`s2`(IN in_name VARCHAR(20))
    /*LANGUAGE SQL
    | [NOT] DETERMINISTIC
    | { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA }
    | SQL SECURITY { DEFINER | INVOKER }
    | COMMENT 'string'*/
    BEGIN
    SELECT address FROM emp WHERE emp_name = in_name;
    

    END$$

DELIMITER ;

调用存储过程s2

CALL s2('张晓红');

创建一个存储过程avg_sai，有3个参数，分别是dept，gender，接收平均工资，功能查询emp表dept_id为1，gender为男的平均工资

DELIMITER $$

CREATE
    /*[DEFINER = { user | CURRENT_USER }]*/
    PROCEDURE `db_view`.`avg_sai`(IN in_dept_id INT,in_gender VARCHAR(2))
    /*LANGUAGE SQL
    | [NOT] DETERMINISTIC
    | { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA }
    | SQL SECURITY { DEFINER | INVOKER }
    | COMMENT 'string'*/
    BEGIN
    SELECT AVG(salary)FROM
    (SELECT * FROM emp WHERE dept_id = in_dept_id) a 
    WHERE gender = in_gender;

    END$$

DELIMITER ;

调用存储过程avg_sai

CALL avg_sai(1,'男');

删除以上存储过程

DROP PROCEDURE s1;
DROP PROCEDURE s2;
DROP PROCEDURE avg_sai;