MySQLケースコンバット-MySQLデータベースビュー強化演習

MySQLデータベースビュー強化演習

序文

この環境は、
特定の構築のためにMySQL-5.7.14を構築するためのCentos7.8システムに基づいています。MySQL-5.7.14環境構築を参照してください。



	步骤1:创建学生表stu,插入3条记录。
		CREATE TABLE stu 

	(

	s_id INT PRIMARY KEY,

	s_name VARCHAR(20),

	addr VARCHAR(50),

	tel VARCHAR(50)

	); 

	INSERT INTO stu 

	VALUES(1,'XiaoWang','Henan','0371-12345678'),

	(2,'XiaoLi','Hebei','13889072345'),

	(3,'XiaoTian','Henan','0371-12345670');
	
	步骤2:创建报名表sign,插入3条记录。
		CREATE TABLE sign 

	(

	s_id INT PRIMARY KEY,

	s_name VARCHAR(20),

	s_sch VARCHAR(50),

	s_sign_sch VARCHAR(50)

	); 

	INSERT INTO sign 

	VALUES(1,'XiaoWang','Middle School1','Peking University'),

	(2,'XiaoLi','Middle School2','Tsinghua University'),

	(3,'XiaoTian','Middle School3','Tsinghua University');

	步骤3:创建成绩表stu_mark,插入3条记录。
	CREATE TABLE stu_mark (s_id INT PRIMARY KEY ,s_name VARCHAR(20) ,mark int ); 

	INSERT INTO stu_mark VALUES(1,'XiaoWang',80),(2,'XiaoLi',71),(3,'XiaoTian',70);

	步骤4:创建考上Peking University的学生的视图
	mysql> create view Peking_stu(学生,学校)
		-> as select s_name,s_sign_sch from sign
		-> where s_sign_sch='Peking University';

	步骤5:创建考上Tsinghua University的学生的视图
		mysql> create view Tsinghua_stu(学生,学校)
		-> as select s_name,s_sign_sch from sign
		-> where s_sign_sch='Tsinghua University';	

	步骤6:XiaoTian的成绩在录入的时候录入错误多录了50分,对其录入成绩进行更正。
		创建视图
		mysql> create view stu_view_mark
		-> as select * from stu_mark;
		修改成绩
		mysql> update stu_mark
		-> set mark=20
		-> where s_name='xiaotian';
		
		
		

	步骤7:查看更新过后视图和表的情况。
		mysql> select * from stu_mark;
		+------+----------+------+
		| s_id | s_name   | mark |
		+------+----------+------+
		|    1 | XiaoWang |   80 |
		|    2 | XiaoLi   |   71 |
		|    3 | XiaoTian |   20 |
		+------+----------+------+
		3 rows in set (0.00 sec)
		
		mysql> select * from stu_view_mark;
		+------+----------+------+
		| s_id | s_name   | mark |
		+------+----------+------+
		|    1 | XiaoWang |   80 |
		|    2 | XiaoLi   |   71 |
		|    3 | XiaoTian |   20 |
		+------+----------+------+
		3 rows in set (0.00 sec)


	步骤8:查看视图的创建信息。
		mysql> show create view Peking_stu\G
		mysql> show create view Tsinghua_stu\G
		mysql> show create view stu_view_mark\G

	步骤9:删除创建的视图。
		mysql> drop view Peking_stu;

		mysql> drop view Tsinghua_stu;

		mysql> drop view stu_view_mark;

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転載: blog.csdn.net/XY0918ZWQ/article/details/113532262