修改视图

使用CREATE OR REPLACE VIEW 子句修改视图

CREATE OR REPLACE VIEW vu_emp1
AS
SELECT employee_id,last_name,salary,email
FROM emps
WHERE salary > 7000;

使用ALTER VIEW方式修改视图

ALTER VIEW vu_emp1
AS 
SELECT employee_id,last_name,salary,email,hire_date
FROM emps;

删除视图

SHOW TABLES;
DROP VIEW vu_emp4;
DROP VIEW IF EXISTS vu_emp2,vu_emp3;