编辑代码

CREATE DATABASE test;
use test;

# 创建 employment_history 表 #
    CREATE TABLE  employment_history (  
    staff_id INT,
    start_date DATETIME, 
    end_date DATETIME, 
    employment_id VARCHAR(10), 
    section_id INT
    );
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (102, '1993-01-13', '1998-07-24','IT_PROG', 60);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (101, '1989-09-21', '1993-10-27','AC_ACCOUNT', 110);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (101, '1993-10-28', '1997-03-15','AC_MGR', 110);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (201, '1996-02-17', '1999-12-19','MK_REP', 20);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (114, '1998-03-24', '1999-12-31','ST_CLERK', 50);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (122, '1999-01-01', '1999-12-31','ST_CLERK', 50);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (200, '1987-09-17', '1993-06-17','AD_ASST', 90);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (176, '1998-03-24', '1998-12-31','SA_REP', 80);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (176, '1999-01-01', '1999-12-31','SA_MAN', 80);
insert into employment_history (staff_id, start_date, end_date, employment_id,section_id)values (200, '1994-07-01', '1998-12-31','AC_ACCOUNT', 90);

# 创建 sections 表 #
	CREATE TABLE sections ( 
	section_id INT not null, 
	section_name VARCHAR(30), 
	manager_id INT,
	place_id INT
	);
	insert into sections (section_id, section_name, manager_id, place_id)values (10, 'Administration', 200, 1700); 
	insert into sections (section_id, section_name, manager_id, place_id)values (20, 'Marketing', 201, 1800); 
	insert into sections (section_id, section_name, manager_id, place_id)values (30, 'Purchasing', 114, 1700);
	insert into sections (section_id, section_name, manager_id, place_id)values (40, 'Human Resources', 203, 2400); 
	insert into sections (section_id, section_name, manager_id, place_id)values (50, 'Shipping', 121, 1500);
	insert into sections (section_id, section_name, manager_id, place_id)values (60, 'IT', 103, 1400);

# 创建  areas 表 #
    CREATE TABLE  areas (  
    area_id INT,
    area_name VARCHAR(25)
    );
insert into areas (area_id, area_name)values (1, 'Europe'); 
insert into areas (area_id, area_name)values (2, 'Americas'); 
insert into areas (area_id, area_name)values (3, 'Asia'); 

# 创建 employments 表 #
    CREATE TABLE  employments (  
    employment_id VARCHAR(10) not null, 
    employment_title VARCHAR(35), 
    min_salary INT(6),
    max_salary INT(6)
    );
insert into employments (employment_id, employment_title, min_salary, max_salary)values ('AD_VP', 'Administration Vice President', 15000, 30000);
insert into employments (employment_id, employment_title, min_salary, max_salary)values ('AD_ASST', 'Administration Assistant', 3000, 6000);
insert into employments (employment_id, employment_title, min_salary, max_salary)values ('FI_MGR', 'Finance Manager', 8200, 16000);
insert into employments (employment_id, employment_title, min_salary, max_salary)values ('FI_ACCOUNT', 'Accountant', 4200, 9000);

 # 创建 states 表 #
    CREATE TABLE states (  
    state_id CHAR(2), 
    state_name VARCHAR(40), 
    area_id INT,
    constraint state_c_id_pk 
    primary key (state_ID)
    );
insert into states (state_id, state_name, area_id)values ('CA', 'Canada', 2); 
insert into states (state_id, state_name, area_id)values ('CH', 'Switzerland', 1); 
insert into states (state_id, state_name, area_id)values ('CN', 'China', 3);  
insert into states (state_id, state_name, area_id)values ('DE', 'Germany', 1); 
insert into states (state_id, state_name, area_id)values ('DK', 'Denmark', 1); 

 # 创建 staffs 表 #
    CREATE TABLE staffs (  
    staff_id INT(6) not null, 
    first_name VARCHAR(20), 
    last_name VARCHAR(25), 
    email VARCHAR(25),
    phone_number VARCHAR(20), 
    hire_date DATETIME, 
    employment_id VARCHAR(10), 
    salary DECIMAL(8,2), 
    commission_pct DECIMAL(2,2), 
    manager_id INT(6),
    section_id INT(4), 
    graduated_name VARCHAR(60)
    );
insert into staffs (staff_id, first_name, last_name, email, phone_number, hire_date,employment_id, salary, commission_pct, manager_id, section_id)values (200, 'Jennifer', 'Whalen', 'JWHALEN', '515.123.4444',  str_to_date('17-09-1987','%d-%m-%Y'), 'AD_ASST', 4400.00, null, 101, 10);
insert into staffs (staff_id, first_name, last_name, email, phone_number, hire_date,employment_id, salary, commission_pct, manager_id, section_id)values (201, 'Michael', 'Hartstein', 'MHARTSTE', '515.123.5555',  str_to_date('17-02-1996','%d-%m-%Y'), 'MK_MAN', 13000.00, null, 100, 20);
insert into staffs (staff_id, first_name, last_name, email, phone_number, hire_date,employment_id, salary, commission_pct, manager_id, section_id)values (202, 'Pat', 'Fay', 'PFAY', '603.123.6666', str_to_date('17-08-1997', '%d-%m-%Y'),'MK_REP', 6000.00, null, 201, 20);
insert into staffs (staff_id, first_name, last_name, email, phone_number, hire_date,employment_id, salary, commission_pct, manager_id, section_id)values (203, 'Susan', 'Mavris', 'SMAVRIS', '515.123.7777', str_to_date('07-06-1994', '%d-%m-%Y'), 'HR_REP', 6500.00, null, 101, 40);

# 上午实验结果 #
# SELECT * FROM  employment_history;
# SELECT * FROM  sections;
# SELECT * FROM  places;
# SELECT * FROM  areas;
# SELECT * FROM  college;
# SELECT * FROM  employments;
# SELECT * FROM  states;
# SELECT * FROM  staffs;

# 2024年3月23日下午：实验练习结果（不显示） #
# SELECT staff_id,first_name,hire_date,salary FROM staffs WHERE HIRE_DATE>'1995-01-01 00:00:00'and salary>'5000';
# SELECT staff_id,first_name,EMPLOYMENT_ID FROM staffs where EMPLOYMENT_ID = 'AD_ASST'

# 2024年3月23日下午：创建 places 表 #
    CREATE TABLE places (  
    place_id INT not null, 
    street_address VARCHAR(40),
    postal_code VARCHAR(12),
    city VARCHAR(30),
    state_province VARCHAR(25), 
    state_id CHAR(2)
    );
insert into places (place_id, street_address, postal_code, city, state_province,state_id)values (1, '呈贡', '678000', '昆明', '云南', '中国');
insert into places (place_id, street_address, postal_code, city, state_province,state_id)values (2, '隆阳', '678014', '保山', '云南', '中国');
insert into places (place_id, street_address, postal_code, city, state_province,state_id)values (3, '玉龙', '278015', '大理', '云南', '中国');
insert into places (place_id, street_address, postal_code, city, state_province,state_id)values (4, '泸沽', '123458', '玉溪', '云南', '中国');
insert into places (place_id, street_address, postal_code, city, state_province,state_id)values (5, '隆阳', '678014', '腾冲', '四川', '美国');
# SELECT * FROM  places;

# 1.信息查询。查询state_province='云南'的places信息 #
# SELECT place_id, street_address, postal_code, city, state_province,state_id FROM places WHERE state_province='云南';
# SELECT street_address, city FROM places;

# 2.错误信息修改。若street_address='隆阳'的时候，修改city='保山',state_province='云南',state_id='中国' #
# UPDATE places SET city='保山',state_province='云南',state_id='中国' WHERE street_address='隆阳';
# SELECT * FROM places WHERE street_address='隆阳';

# 3.信息删除。删除places表中的street_address='泸沽'的数据 #
# DELETE FROM places WHERE street_address='泸沽';
# SELECT * FROM places;

# 2024年3月24日上午：创建 students 表 #
    CREATE TABLE students (  
    id INT, 
    class_id INT,
    name VARCHAR(12),
    gender VARCHAR(30),
    score INT
    );
insert into students (id,class_id,name,gender,score)values (1,1,'小明','M',90);
insert into students (id,class_id,name,gender,score)values (2,1,'小红','F',95);
insert into students (id,class_id,name,gender,score)values (3,1,'小军','M',88);
insert into students (id,class_id,name,gender,score)values (4,1,'小米','F',73);
insert into students (id,class_id,name,gender,score)values (5,2,'小白','F',81);
insert into students (id,class_id,name,gender,score)values (6,2,'小兵','M',55);
insert into students (id,class_id,name,gender,score)values (7,2,'小林','M',85);
insert into students (id,class_id,name,gender,score)values (8,3,'小新','F',91);
insert into students (id,class_id,name,gender,score)values (9,3,'小王','M',89);
insert into students (id,class_id,name,gender,score)values (10,3,'小丽','F',85);
# SELECT * FROM students;
# 2024年3月24日上午：创建 classes 表 #
    CREATE TABLE classes (  
    id INT, 
    name VARCHAR(12),
    teacher VARCHAR(12)
    );
insert into classes (id,name,teacher)values (1,'一班','张老师'); 
insert into classes (id,name,teacher)values (2,'二班','刘老师');
insert into classes (id,name,teacher)values (3,'三班','杨老师');
# SELECT * FROM classes;

# （一）按条件查询（WHERE）#
# SELECT * FROM students WHERE score >=90;
# SELECT * FROM students WHERE score >=90 AND gender = 'M';
# SELECT * FROM students WHERE score >= 90 OR gender = 'M';
# SELECT * FROM students WHERE (score < 80 OR score > 90) AND class_id = 1;

# （二）投影查询（SELECT * FROM <表名> WHERE <条件>）#
# SELECT id, score, name FROM students;

# （三）排序查询（ORDER BY）#
# SELECT id, name, gender, score, class_id FROM students WHERE class_id = 1 OR class_id = 2 ORDER BY score DESC;

# （四）分页查询（LIMIT <N-M> OFFSET <M>）#
# SELECT * FROM students;
# SELECT id, class_id, name, gender, score FROM students ORDER BY class_id DESC LIMIT 5 OFFSET 0;

# （五）聚合查询（COUNT(*)）#
# SELECT * FROM students;
# SELECT COUNT(*) FROM students;
# SELECT COUNT(*) boys FROM students WHERE gender = 'M';
# SELECT class_id,avg(score) FROM students GROUP BY class_id;
# SELECT class_id,gender,avg(score) FROM students GROUP BY class_id,gender;

# （六）多表查询（SELECT * FROM <表1> <表2>）#
# SELECT
    # students.id sid,
    # students.name,
    # students.gender,
    # students.score,
    # classes.id cid,
    # classes.name cname
# FROM students, classes;

# （七）链接查询（SELECT * FROM <表1> <表2>）#
SELECT s.id, s.name, s.class_id, c.name class_name, s.gender, s.score
FROM students s
RIGHT OUTER JOIN classes c
ON s.class_id = c.id;