Mysql练习-视图的操作
一、练习要求
① 创建学生表stu，插入3条记录
② 创建报名表sign，插入3条记录
③ 创建成绩表stu_mark，插入3条记录
④ 创建考上Peking University的学生的视图
⑤ 创建考上Tsinghua University的学生的视图
⑥ XiaoTian的成绩在录入的时候因录入错误多录了50分，对其成绩进行更正
⑦ 查看更新后视图和表的情况
⑧ 查看视图的创建信息
⑨ 删除创建的视图
【Mysql练习-视图的操作】
stu表结构
| 字段名 | 数据类型 | 主键 | 外键 | 非空 | 唯一 | 自增 |
|---|---|---|---|---|---|---|
| s_id | INT(11) | 是 | 否 | 是 | 是 | 否 |
| s_name | VARCHAR(20) | 否 | 否 | 是 | 否 | 否 |
| addr | VARCHAR(50) | 否 | 否 | 是 | 否 | 否 |
| tel | VARCHAR(50) | 否 | 否 | 是 | 否 | 否 |
stu表内容
| s_id | s_name | addr | tel |
|---|---|---|---|
| 1 | XiaoWang | Henan | 0371-12345678 |
| 2 | XiaoLi | Hebei | 13889072345 |
| 3 | ZhengGu | Henan | 0371-1234570 |
sign表结构
| 字段名 | 数据类型 | 主键 | 外键 | 非空 | 唯一 | 自增 |
|---|---|---|---|---|---|---|
| s_id | INT(11) | 是 | 否 | 是 | 是 | 否 |
| s_name | VARCHAR(20) | 否 | 否 | 是 | 否 | 否 |
| s_sch | VARCHAR(50) | 否 | 否 | 是 | 否 | 否 |
| s_sign_sch | VARCHAR(50) | 否 | 否 | 是 | 否 | 否 |
sign表内容
| s_id | s_name | s_sch | s_sign_sch |
|---|---|---|---|
| 1 | XiaoWang | Middle School1 | Peking University |
| 2 | XiaoLi | Middle School2 | Tsinghua University |
| 3 | ZhengGu | Middle School3 | Tsinghua University |
stu_mark表结构
| 字段名 | 数据类型 | 主键 | 外键 | 非空 | 唯一 | 自增 |
|---|---|---|---|---|---|---|
| s_id | INT(11) | 是 | 否 | 是 | 是 | 否 |
| s_name | VARCHAR(20) | 否 | 否 | 是 | 否 | 否 |
| mark | INT(11) | 否 | 否 | 是 | 否 | 否 |
stu_mark表内容
| s_id | s_name | mark |
|---|---|---|
| 1 | XiaoWang | 80 |
| 2 | XiaoLi | 71 |
| 3 | ZhengGu | 70 |
二、操作记录
创建学生表stu，插入3条记录
mysql> CREATE TABLE stu
-> (
-> s_id INT PRIMARY KEY,
-> s_name VARCHAR(20),
-> addr VARCHAR(50),
-> tel VARCHAR(50)
-> );
Query OK, 0 rows affected (0.28 sec)mysql>
mysql> INSERT INTO stu
-> VALUES(1,'XiaoWang','Henan','0371-12345678'),
-> (2,'XiaoLi','Hebei','13889072345'),
-> (3,'XiaoTian','Henan','0371-12345670');
Query OK, 3 rows affected (0.08 sec)
Records: 3Duplicates: 0Warnings: 0mysql>
创建报名表sign，插入3条记录
mysql> CREATE TABLE sign
-> (
-> s_id INT PRIMARY KEY,
-> s_name VARCHAR(20),
-> s_sch VARCHAR(50),
-> s_sign_sch VARCHAR(50)
-> );
Query OK, 0 rows affected (0.32 sec)mysql>
mysql> INSERT INTO sign
-> VALUES(1,'XiaoWang','Middle School1','Peking University'),
-> (2,'XiaoLi','Middle School2','Tsinghua University'),
-> (3,'XiaoTian','Middle School3','Tsinghua University');
Query OK, 3 rows affected (0.07 sec)
Records: 3Duplicates: 0Warnings: 0mysql>
创建成绩表stu_mark，插入3条记录
mysql> CREATE TABLE stu_mark (s_id INT PRIMARY KEY ,s_name VARCHAR(20) ,mark int );
Query OK, 0 rows affected (0.24 sec)mysql>
mysql> INSERT INTO stu_mark VALUES(1,'XiaoWang',80),(2,'XiaoLi',71),(3,'XiaoTian',70);
Query OK, 3 rows affected (0.11 sec)
Records: 3Duplicates: 0Warnings: 0mysql>
创建考上Peking University的学生的视图
mysql> CREATE VIEW beida (id,name,mark,sch)
-> AS SELECT stu_mark.s_id,stu_mark.s_name,stu_mark.mark, sign.s_sign_sch
-> FROM stu_mark ,sign
-> WHERE stu_mark.s_id=sign.s_id AND stu_mark.mark>=41 AND sign.s_sign_sch='Peking University';
Query OK, 0 rows affected (0.06 sec)mysql>
创建考上Tsinghua University的学生的视图
mysql> CREATE VIEW qinghua (id,name,mark,sch)
-> AS SELECT stu_mark.s_id, stu_mark.s_name, stu_mark.mark, sign.s_sign_sch
-> FROM stu_mark ,sign
-> WHERE stu_mark.s_id=sign.s_idAND stu_mark.mark>=40 AND sign.s_sign_sch='Tsinghua University';
Query OK, 0 rows affected (0.05 sec)mysql>
XiaoTian的成绩在录入的时候因录入错误多录了50分，对其成绩进行更正
mysql> UPDATE stu_mark SET mark = mark-50 WHERE stu_mark.s_name ='XiaoTian';
Query OK, 1 row affected (0.06 sec)
Rows matched: 1Changed: 1Warnings: 0mysql>
查看更新后视图和表的情况
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 qinghua;
+----+--------+------+---------------------+
| id | name| mark | sch|
+----+--------+------+---------------------+
|2 | XiaoLi |71 | Tsinghua University |
+----+--------+------+---------------------+
1 row in set (0.00 sec)mysql> SELECT * FROM beida;
+----+----------+------+-------------------+
| id | name| mark | sch|
+----+----------+------+-------------------+
|1 | XiaoWang |80 | Peking University |
+----+----------+------+-------------------+
1 row in set (0.00 sec)mysql>
查看视图的创建信息
mysql> SELECT * FROM information_schema.views where table_name = 'beida'\G
*************************** 1. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: index_test
TABLE_NAME: beida
VIEW_DEFINITION: select `index_test`.`stu_mark`.`s_id` AS `id`,`index_test`.`stu_mark`.`s_name` AS `name`,`index_test`.`stu_mark`.`mark` AS `mark`,`index_test`.`sign`.`s_sign_sch` AS `sch` from `index_test`.`stu_mark` join `index_test`.`sign` where ((`index_test`.`stu_mark`.`s_id` = `index_test`.`sign`.`s_id`) and (`index_test`.`stu_mark`.`mark` >= 41) and (`index_test`.`sign`.`s_sign_sch` = 'Peking University'))
CHECK_OPTION: NONE
IS_UPDATABLE: YES
DEFINER: root@localhost
SECURITY_TYPE: DEFINER
CHARACTER_SET_CLIENT: gbk
COLLATION_CONNECTION: gbk_chinese_ci
*************************** 2. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: view
TABLE_NAME: beida
VIEW_DEFINITION: select `view`.`stu_mark`.`s_id` AS `id`,`view`.`stu_mark`.`s_name` AS `name`,`view`.`stu_mark`.`mark` AS `mark`,`view`.`sign`.`s_sign_sch` AS `sch` from `view`.`stu_mark` join `view`.`sign` where ((`view`.`sign`.`s_id` = `view`.`stu_mark`.`s_id`) and (`view`.`sign`.`s_sign_sch` = 'Peking University') and (`view`.`stu_mark`.`mark` >= 41))
CHECK_OPTION: NONE
IS_UPDATABLE: YES
DEFINER: root@localhost
SECURITY_TYPE: DEFINER
CHARACTER_SET_CLIENT: gbk
COLLATION_CONNECTION: gbk_chinese_ci
2 rows in set (0.00 sec)mysql> SELECT * FROM information_schema.views where table_name = 'qinghua'\G
*************************** 1. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: index_test
TABLE_NAME: qinghua
VIEW_DEFINITION: select `index_test`.`stu_mark`.`s_id` AS `id`,`index_test`.`stu_mark`.`s_name` AS `name`,`index_test`.`stu_mark`.`mark` AS `mark`,`index_test`.`sign`.`s_sign_sch` AS `sch` from `index_test`.`stu_mark` join `index_test`.`sign` where ((`index_test`.`stu_mark`.`s_id` = `index_test`.`sign`.`s_id`) and (`index_test`.`stu_mark`.`mark` >= 40) and (`index_test`.`sign`.`s_sign_sch` = 'Tsinghua University'))
CHECK_OPTION: NONE
IS_UPDATABLE: YES
DEFINER: root@localhost
SECURITY_TYPE: DEFINER
CHARACTER_SET_CLIENT: gbk
COLLATION_CONNECTION: gbk_chinese_ci
*************************** 2. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: view
TABLE_NAME: qinghua
VIEW_DEFINITION: select `view`.`stu_mark`.`s_id` AS `id`,`view`.`stu_mark`.`s_name` AS `name`,`view`.`stu_mark`.`mark` AS `mark`,`view`.`sign`.`s_sign_sch` AS `sch` from `view`.`stu_mark` join `view`.`sign` where ((`view`.`sign`.`s_id` = `view`.`stu_mark`.`s_id`) and (`view`.`sign`.`s_sign_sch` = 'Tsinghua University') and (`view`.`stu_mark`.`mark` >= 40))
CHECK_OPTION: NONE
IS_UPDATABLE: YES
DEFINER: root@localhost
SECURITY_TYPE: DEFINER
CHARACTER_SET_CLIENT: gbk
COLLATION_CONNECTION: gbk_chinese_ci
2 rows in set (0.00 sec)mysql>
删除创建的视图
mysql> DROP VIEW beida;
Query OK, 0 rows affected (0.00 sec)mysql> DROP VIEW qinghua;
Query OK, 0 rows affected (0.00 sec)mysql>
推荐阅读
- MySQL高级优化|MySQL（索引优化、查询优化）
- #|MySQL-高级-9 索引优化及查询优化
- 数据库相关|Mysql数据查询优化——索引优化
- java提高|第07章 InnoDB数据存储结构【2.索引及调优篇】【MySQL高级】
- mysql|mysql 索引优化 2_mysql调优二-索引优化
- mysql优化varchar索引_Mysql调优-4通过索引进行优化
- mysql|mysql 字符串 索引优化_MySQL高级之索引优化分析
- Mysql优化|Mysql-索引优化
- HIVE综合练习-SQL练习之影评案例
- 正则表达式完整入门教程，含在线练习