652 lines
18 KiB
Markdown
652 lines
18 KiB
Markdown
### 练习一
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```sql
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#(1)创建数据库
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CREATE DATABASE test04_Market DEFAULT CHARACTER SET utf8;
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USE test04_Market;
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#(2)创建数据表
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CREATE TABLE customers(
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c_num INT(11) PRIMARY KEY AUTO_INCREMENT,
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c_name VARCHAR(50),
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c_contact VARCHAR(50),
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c_city VARCHAR(50),
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c_birth DATETIME NOT NULL
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);
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#(3)更改字段的位置
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#AFTER/BEFORE 字段名 设置位置在指定字段前/后
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ALTER TABLE 表名 MODIFY 字段名 数据类型 AFTER/BEFORE 字段名;
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ALTER TABLE customers MODIFY c_contact VARCHAR(50) AFTER c_birth;
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#(4)更改字段的数据类型
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ALTER TABLE customers MODIFY c_name VARCHAR(70);
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#(5)更改字段名
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ALTER TABLE customers CHANGE c_contact c_phone VARCHAR(50);
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#(6)添加字段
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ALTER TABLE customers ADD c_gender CHAR(1);
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#(7)更改表名
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ALTER TABLE customers RENAME TO customers_info;
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#(8)删除字段
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ALTER TABLE customers_info DROP c_city;
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```
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```sql
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#(1)创建表时 添加外键约束并指定外键约束名称
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CREATE TABLE orders(
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o_num INT(11) PRIMARY KEY AUTO_INCREMENT,
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o_date DATE,
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c_id INT(11),
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CONSTRAINT fk_cid FOREIGN KEY(c_id) REFERENCES customers_info(c_num)
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);
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#(2)
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#删除指定外键
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ALTER TABLE orders DROP FOREIGN KEY orders_ibfk_1;
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#删除指定表
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DROP TABLE orders;
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```
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---
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### 练习二
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```sql
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#(1)创建表、插入记录
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CREATE TABLE pet(
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`name` VARCHAR(20) NOT NULL COMMENT '宠物名称',
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`owner` VARCHAR(20) COMMENT '宠物主人',
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species VARCHAR(20) NOT NULL COMMENT '种类',
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sex CHAR(1) NOT NULL COMMENT '性别',
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birth YEAR NOT NULL COMMENT '出生日期',
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death YEAR COMMENT '死亡日期'
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);
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INSERT INTO pet()
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VALUES
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('Fluffy', 'Harold', 'cat', 'f', 2003, 2010),
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('Claws', 'Gwen', 'cat', 'm', 2004,NULL ),
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('Buffy', NULL, 'dog', 'f', 2009, NULL),
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('Fang', 'Benny', 'dog', 'm', 2000, NULL),
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('Bowser', 'Diane', 'dog', 'm', 2003, 2009),
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('Chirpy', NULL, 'bird', 'f', 2008, NULL);
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#(2)更新记录
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UPDATE pet
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SET `owner` = 'Kevin'
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WHERE `name` = 'Fang';
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#(3)
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UPDATE pet
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SET `owner` = 'Kevin'
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WHERE `owner` IS NULL;
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#(4)
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DELETE FROM pet
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WHERE death IS NOT NULL;
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#(5)
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TRUNCATE pet;
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```
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---
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### 练习三
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```sql
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#1.创建数据库
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CREATE DATABASE test_compay DEFAULT CHARACTER SET utf8;
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#2.创建表
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CREATE TABLE department(
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depid INT PRIMARY KEY AUTO_INCREMENT,
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depname VARCHAR(20) NOT NULL,
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deinfo VARCHAR(50)
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);
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CREATE TABLE employee(
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empid INT PRIMARY KEY AUTO_INCREMENT,
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`name` VARCHAR(20) NOT NULL,
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sex CHAR(1) NOT NULL DEFAULT '男',
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title VARCHAR(20) NOT NULL,
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birthday DATE NOT NULL,
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depid INT,
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CONSTRAINT fk_eid_did FOREIGN KEY(depid) REFERENCES department(depid)
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);
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CREATE TABLE salary(
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empid INT,
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basesalary DECIMAL(10, 2),
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titleSalary DECIMAL(10, 2),
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decuction DECIMAL(10, 2)
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);
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#3添加外键并设置级联更新、级联删除
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ALTER TABLE salary ADD CONSTRAINT fk_sal_eid FOREIGN KEY(empid)
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REFERENCES employee(empid) ON UPDATE CASCADE ON DELETE CASCADE;
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#4插入记录
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INSERT INTO department (depid, depname, deinfo)
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VALUES
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(111, '生产部', NULL),
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(222, '销售部', NULL),
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(333, '人事部', NULL),
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(444, '财务部', '负责公司财务管理'),
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(555, '技术部', '负责技术研发与支持'),
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(666, '市场部', '负责市场推广与品牌建设'),
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(777, '客服部', '负责客户服务与支持'),
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(888, '采购部', '负责公司物资采购'),
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(999, '法务部', '负责公司法律事务'),
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(1010, '行政部', '负责公司日常行政管理'),
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(1011, '研发部', '负责新产品研发'),
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(1012, '培训部', '负责员工培训与发展');
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INSERT INTO employee (empid, name, sex, title, birthday, depid)
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VALUES
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(1001, '张三', '男', '高级工程师', '1975-1-1', 111),
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(1002, '李四', '女', '助工', '1985-1-1', 111),
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(1003, '王五', '男', '工程师', '1978-11-11', 222),
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(1004, '赵六', '男', '工程师', '1999-1-1', 222),
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(1005, '陈七', '女', '会计师', '1980-5-15', 444),
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(1006, '刘八', '男', '软件工程师', '1990-8-20', 555),
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(1007, '孙九', '女', '市场经理', '1985-12-25', 666),
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(1008, '周十', '男', '客服专员', '1992-3-10', 777),
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(1009, '吴十一', '女', '采购经理', '1988-7-22', 888),
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(1010, '郑十二', '男', '法务顾问', '1983-9-30', 999),
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(1011, '王十三', '女', '行政助理', '1995-4-18', 1010),
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(1012, '李十四', '男', '研发工程师', '1991-11-5', 1011),
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(1013, '赵十五', '女', '培训讲师', '1987-6-12', 1012),
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(1014, '孙十六', '男', '技术支持', '1993-2-14', 555),
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(1015, '杨十七', '女', '销售代表', '1994-8-8', 222);
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INSERT INTO salary (empid, basesalary, titleSalary, decuction)
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VALUES
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(1001, 2200, 1100, 200),
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(1002, 1200, 200, NULL),
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(1003, 2900, 700, 200),
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(1004, 1950, 700, 150),
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(1005, 2500, 800, 100),
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(1006, 3000, 1200, 250),
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(1007, 2800, 1000, 200),
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(1008, 1800, 300, 50),
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(1009, 3200, 900, 300),
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(1010, 3500, 1000, 400),
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(1011, 2000, 400, 100),
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(1012, 3100, 1100, 200),
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(1013, 2700, 800, 150),
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(1014, 2300, 700, 100),
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(1015, 2600, 600, 200);
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```
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```sql
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#5
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SELECT e.empid, e.`name`, e.title, d.depname, s.basesalary + s.titleSalary, s.basesalary + s.titleSalary-IFNULL(s.decuction, 0)
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FROM employee e, department d, salary s
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WHERE e.depid = d.depid AND e.empid = s.empid;
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#6
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SELECT e.`name`, s.basesalary
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FROM employee e, department d, salary s
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WHERE e.depid = d.depid AND e.empid = s.empid AND d.depname = '销售部';
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#7
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SELECT *
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FROM employee e
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WHERe e.`name` LIKE '张%' AND TIMESTAMPDIFF(YEAR,e.birthday, NOW()) < 40;
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#8
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SELECT e.`name`, s.basesalary, s.titleSalary
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FROM employee e, salary s
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WHERE e.sex = '男' AND e.empid AND s.empid;
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#9
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SELECT e.`name`, e.title, d.depname
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FROM employee e, department d, salary s
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WHERE e.depid = d.depid AND e.empid = s.empid AND s.basesalary < 2000;
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#10
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SELECT COUNT(*)
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FROM employee;
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#11
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SELECT COUNT(*)
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FROM department d;
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#12
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SELECT AVG(s.basesalary + s.titleSalary), MAX(s.basesalary + s.titleSalary), MIN(s.basesalary + s.titleSalary)
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FROM employee e, salary s
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WHERE e.empid = s.empid;
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#13
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SELECT d.depname, AVG(s.basesalary + s.titleSalary)
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FROM employee e, salary s, department d
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WHERE e.empid = s.empid AND e.depid = d.depid
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GROUP BY d.depid;
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#14
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SELECT d.depname, AVG(s.basesalary + s.titleSalary) avg
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FROM employee e, salary s, department d
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WHERE e.empid = s.empid AND e.depid = d.depid
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GROUP BY d.depid
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HAVING avg<2000;
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#15
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SELECT e.empid, e.`name`, s.basesalary, s.titleSalary, s.decuction
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FROM employee e, salary s, department d
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WHERE e.empid = s.empid AND e.depid = d.depid
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ORDER BY s.titleSalary, s.basesalary;
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#16
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SELECT e.empid, e.`name`, e.birthday,
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IF(YEAR(e.birthday) < 1980, '老年',
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IF(YEAR(e.birthday)< 1990, '中年', '青壮年'))
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FROM employee e;
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#17
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SELECT e.*, depname
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FROM employee e, department d
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WHERE e.depid = d.depid;
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#18
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SELECT d.*, e.*
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FROM employee e, department d
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WHERE e.depid = d.depid;
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#19
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SELECT *
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FROM employee e
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WHERE e.title LIKE '%工程师%' AND e.sex = '男';
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#20
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SELECT d.depname, e.sex, COUNT(*), AVG(s.basesalary)
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FROM employee e, department d, salary s
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WHERE e.depid = d.depid AND e.empid = s.empid
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GROUP BY d.depid, e.sex;
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```
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---
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### 练习四
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```sql
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#1
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CREATE DATABASE test_school DEFAULT CHARACTER SET 'UTF8';
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#2
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DROP TABLE department;
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CREATE TABLE department(
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depNo INT(10) PRIMARY KEY COMMENT '部门号',
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depName VARCHAR(50) NOT NULL COMMENT '部门名称',
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depNote VARCHAR(20) COMMENT '部门备注'
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);
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CREATE TABLE teacher(
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number INT PRIMARY KEY COMMENT '教工号',
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`name` VARCHAR(30) NOT NULL COMMENT '姓名',
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sex VARCHAR(4) COMMENT '性别',
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birth DATE COMMENT '出生日期',
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depNo INT COMMENT '部门号',
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salary FLOAT COMMENT '工资',
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address VARCHAR(100) COMMENT '家庭住址'
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);
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INSERT INTO department()
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VALUES
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(601, '软件技术系', '软件技术等专业'),
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(602, '网络技术系', '多媒体技术等专业'),
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(603, '艺术设计系', '广告艺术设计等专业'),
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(604, '管理工程系', '连锁经营管理等专业');
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INSERT INTO teacher()
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VALUES
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(2001, 'Tom', '女', '1970-01-10', 602, 4500, '四川省绵阳市'),
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(2002, 'Lucy', '男', '1983-12-18', 601, 2500, '北京市昌平区'),
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(2003, 'Mike', '男', '1990-06-01', 604, 1500, '重庆市渝中区'),
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(2004, 'James', '女', '1980-10-20', 602, 3500, '四川省成都市'),
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(2005, 'Jack', '男', '1975-05-30', 603, 1200, '重庆市南岸区');
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```
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```sql
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#4
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SELECT *
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FROM teacher;
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#5
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SELECT t.number '教工号', d.depName '部门名称'
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FROM teacher t, department d
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WHERE t.depNo = d.depNo AND t.address LIKE '%北京%';
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#6
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SELECT t.number, t.`name`
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FROM teacher t
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ORDER BY t.salary DESC
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LIMIT 1;
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#7
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SELECT t.number, t.`name`
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FROM teacher t
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WHERE t.salary BETWEEN 2500 AND 4000;
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#8
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SELECT t.`name`, t.sex, t.salary
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FROM teacher t, department d
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WHERE t.depNo = d.depNo AND d.depName = '网络技术系';
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```
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---
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### 练习五
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```sql
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-- 创建数据库并设置字符集为 utf8mb4
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CREATE DATABASE test_student CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
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USE test_student;
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-- 创建表 Classes
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CREATE TABLE Classes (
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专业 VARCHAR(50),
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班级 VARCHAR(50),
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姓名 VARCHAR(50),
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性别 VARCHAR(10),
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座位 INT
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);
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-- 向表 Classes 插入数据
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INSERT INTO Classes (专业, 班级, 姓名, 性别, 座位) VALUES
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('计算机网络', '1班', '张三', '男', 8),
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('软件工程', '2班', '李四', '男', 12),
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('计算机维护', '1班', '王五', '男', 9),
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('计算机网络', '2班', 'LILY', '女', 15),
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('软件工程', '1班', '小强', '男', 20),
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('计算机维护', '1班', 'CoCo', '女', 18);
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-- 创建表 Score
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CREATE TABLE Score (
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姓名 VARCHAR(50),
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英语 INT,
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数学 INT,
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语文 INT
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);
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-- 向表 Score 插入数据
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INSERT INTO Score (姓名, 英语, 数学, 语文) VALUES
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('张三', 65, 75, 98),
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('李四', 87, 45, 86),
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('王五', 98, 85, 65),
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('LILY', 75, 86, 87),
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('小强', 85, 60, 58),
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('CoCo', 96, 87, 70);
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-- 创建表 Records
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CREATE TABLE Records (
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姓名 VARCHAR(50),
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记录 VARCHAR(50)
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);
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-- 向表 Records 插入数据
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INSERT INTO Records (姓名, 记录) VALUES
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('小强', '迟到'),
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('小强', '事假'),
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('李四', '旷课'),
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('李四', '旷课'),
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('李四', '迟到'),
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('CoCo', '病假'),
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('LILY', '事假');
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```
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```sql
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#3
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UPDATE score s
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SET s.`语文` = 88
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WHERE s.`姓名` = '张三';
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#4
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SELECT AVG(s.`英语`), AVG(s.`数学`), AVG(s.`语文`)
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FROM classes c, score s
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WHERE c.`姓名` = s.`姓名` AND c.`班级` = 1 AND c.`专业` = '计算机维护';
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#5
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SELECT *
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FROM score s
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WHERE s.`数学` < 60 OR s.`英语` < 60 OR s.`语文` < 60;
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#6
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SELECT *
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FROM score s
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WHERE s.`姓名` IN (
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SELECT r.`姓名`
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FROM records r
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GROUP BY r.`姓名`
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HAVING COUNT(*) > 2
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);
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```
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---
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### 练习六
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```sql
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-- 创建数据库 test_xuankedb 并设置字符集为 utf8mb4
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CREATE DATABASE test_xuankedb CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
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USE test_xuankedb;
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-- 创建学生表 Student
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CREATE TABLE Student (
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Sn0 VARCHAR(20) PRIMARY KEY, -- 学号，主键
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Sname VARCHAR(50), -- 姓名
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Ssex VARCHAR(10), -- 性别
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Sage INT, -- 年龄
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Sdept VARCHAR(50) -- 所在系
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);
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-- 创建课程表 Course
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CREATE TABLE Course (
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Cn0 VARCHAR(20) PRIMARY KEY, -- 课程号，主键
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Cname VARCHAR(100), -- 课程名
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Cpn0 VARCHAR(20), -- 选修课号
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Ccredit INT -- 学分
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);
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-- 创建成绩表 SG
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CREATE TABLE SG (
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Sn0 VARCHAR(20), -- 学号
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Cn0 VARCHAR(20), -- 课程号
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Grade INT, -- 成绩
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PRIMARY KEY (Sn0, Cn0), -- 复合主键 (学号, 课程号)
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FOREIGN KEY (Sn0) REFERENCES Student(Sn0), -- 外键，引用 Student 表
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FOREIGN KEY (Cn0) REFERENCES Course(Cn0) -- 外键，引用 Course 表
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);
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INSERT INTO Student (Sno, Sname, Ssex, Sage, Sdept, Scome) VALUES
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('05001', '张三', '男', 20, '计算机系', '2021-09-01'),
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('05002', '李四', '女', 21, '数学系', '2021-09-01'),
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('05003', '王五', '男', 22, '计算机系', '2021-09-01'),
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('05004', '李洋', '男', 19, '物理系', '2021-09-01'),
|
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('05019', '赵六', '女', 20, '计算机系', '2021-09-01');
|
||
|
||
INSERT INTO Course (Cno, Cname, Cpno, Ccredit) VALUES
|
||
('1', '数据库', NULL, 4),
|
||
('2', '数学', NULL, 3),
|
||
('3', '物理', NULL, 3),
|
||
('4', '操作系统', '1', 4);
|
||
|
||
INSERT INTO SG (Sno, Cno, Grade) VALUES
|
||
('05001', '1', 85),
|
||
('05001', '2', 90),
|
||
('05002', '1', 78),
|
||
('05002', '3', 88),
|
||
('05003', '1', 92),
|
||
('05003', '4', 76),
|
||
('05004', '3', 95),
|
||
('05019', '1', 80),
|
||
('05019', '4', 85);
|
||
```
|
||
|
||
---
|
||
|
||
### 练习七
|
||
|
||
|
||
|
||
|
||
|
||
```sql
|
||
-- 创建数据库 test_library 并设置字符集为 utf8mb4
|
||
CREATE DATABASE test_library CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
|
||
USE test_library;
|
||
|
||
-- 创建表 press（出版社）
|
||
CREATE TABLE press (
|
||
pressid INT PRIMARY KEY, -- 出版社编号，主键
|
||
pressname VARCHAR(100), -- 出版社名称
|
||
address VARCHAR(100) -- 出版社地址
|
||
);
|
||
|
||
-- 创建表 sort（种类）
|
||
CREATE TABLE sort (
|
||
sortno INT PRIMARY KEY, -- 种类编号，主键
|
||
scount INT, -- 数量
|
||
describes VARCHAR(100) -- 描述
|
||
);
|
||
|
||
-- 创建表 book（图书）
|
||
CREATE TABLE book (
|
||
bid INT PRIMARY KEY, -- 图书编号，主键
|
||
bname VARCHAR(100), -- 图书名称
|
||
bsortno INT, -- 种类编号
|
||
pressid INT, -- 出版社编号
|
||
FOREIGN KEY (bsortno) REFERENCES sort(sortno), -- 外键，引用 sort 表
|
||
FOREIGN KEY (pressid) REFERENCES press(pressid) -- 外键，引用 press 表
|
||
);
|
||
|
||
-- 向 press 表插入数据
|
||
INSERT INTO press (pressid, pressname, address) VALUES
|
||
(100, '外研社', '上海'),
|
||
(101, '北大出版社', '北京'),
|
||
(102, '教育出版社', '北京');
|
||
|
||
-- 向 sort 表插入数据
|
||
INSERT INTO sort (sortno, scount, describes) VALUES
|
||
(11, 50, '小说'),
|
||
(12, 100, '科幻'),
|
||
(13, 100, '神话');
|
||
|
||
-- 向 book 表插入数据
|
||
INSERT INTO book (bid, bname, bsortno, pressid) VALUES
|
||
(1, '红与黑', 11, 100),
|
||
(2, '幻城', 12, 102),
|
||
(3, '希腊神话', 13, 102);
|
||
|
||
#5
|
||
SELECT b.*
|
||
FROM book b, press p
|
||
WHERE p.pressid = b.pressid AND p.pressid = 100;
|
||
|
||
#6
|
||
SELECT b.*
|
||
FROM book b, press p
|
||
WHERE p.pressid = b.pressid AND p.pressname = '外研社';
|
||
|
||
#7
|
||
SELECT *
|
||
FROM sort s
|
||
WHERE s.scount > 100;
|
||
|
||
#8
|
||
SELECT p.*
|
||
FROM book b, press p
|
||
WHERE p.pressid = b.pressid
|
||
GROUP BY b.pressid
|
||
HAVING COUNT(*) = (
|
||
SELECT COUNT(*)
|
||
FROM book b, press p
|
||
WHERE p.pressid = b.pressid
|
||
GROUP BY b.pressid
|
||
ORDER BY COUNT(*) DESC
|
||
LIMIT 1
|
||
);
|
||
```
|
||
|
||
---
|
||
|
||
### 练习八
|
||
|
||
|
||
|
||
|
||
|
||
```sql
|
||
-- 创建数据库 test_tour 并设置字符集为 utf8mb4
|
||
CREATE DATABASE test_tour CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
|
||
USE test_tour;
|
||
|
||
-- 创建表 agency（旅行社表）
|
||
CREATE TABLE agency (
|
||
id INT PRIMARY KEY, -- 旅行社编号，主键
|
||
name VARCHAR(100) NOT NULL, -- 旅行社名
|
||
address VARCHAR(100) NOT NULL, -- 旅行社地址
|
||
areaid INT -- 所属区域编号
|
||
);
|
||
|
||
-- 创建表 travel（旅行线路表）
|
||
CREATE TABLE travel (
|
||
tid INT PRIMARY KEY, -- 旅行线路编号，主键
|
||
time VARCHAR(50) NOT NULL, -- 所需时间
|
||
position VARCHAR(100) NOT NULL, -- 目的地
|
||
money FLOAT, -- 花费
|
||
aid INT NOT NULL, -- 所属旅行社编号
|
||
count INT, -- 报名人数
|
||
FOREIGN KEY (aid) REFERENCES agency(id) -- 外键，引用 agency 表
|
||
);
|
||
|
||
-- 向 agency 表插入数据
|
||
INSERT INTO agency (id, name, address) VALUES
|
||
(101, '青年旅行社', '北京海淀'),
|
||
(102, '天天旅行社', '天津海院');
|
||
|
||
-- 向 travel 表插入数据
|
||
INSERT INTO travel (tid, time, position, money, aid, count) VALUES
|
||
(1, '5天', '八达岭', 3000, 101, 10),
|
||
(2, '7天', '水长城', 5000, 101, 14),
|
||
(3, '8天', '水长城', 6000, 102, 11);
|
||
|
||
#4
|
||
SELECT a.*
|
||
FROM travel t, agency a
|
||
WHERE t.aid =a.id
|
||
GROUP BY a.id
|
||
HAVING COUNT(*) = (
|
||
SELECT COUNT(*)
|
||
FROM travel t, agency a
|
||
WHERE t.aid =a.id
|
||
GROUP BY a.id
|
||
ORDER BY COUNT(*) DESC
|
||
LIMIT 1
|
||
);
|
||
|
||
#5
|
||
SELECT t.*
|
||
FROM travel t
|
||
WHERE t.count = (
|
||
SELECT t.count
|
||
FROM travel t
|
||
ORDER BY t.count DESC
|
||
LIMIT 1
|
||
);
|
||
|
||
#6
|
||
SELECT *
|
||
FROM travel t
|
||
WHERE t.money < 5000;
|
||
|
||
#7
|
||
SELECT a.`name`
|
||
FROM travel t, agency a
|
||
WHERE t.aid =a.id AND t.money = (
|
||
SELECT t.money
|
||
FROM travel t, agency a
|
||
WHERE t.aid =a.id
|
||
ORDER BY t.money DESC
|
||
LIMIT 1
|
||
);
|
||
|
||
#8
|
||
SELECT SUM(t.time)
|
||
FROM travel t, agency a
|
||
WHERE t.aid =a.id AND a.`name` = '青年旅行社';
|
||
```
|
||
|