编辑代码

CREATE DATABASE 覃钰芳;
USE 覃钰芳;
CREATE TABLE students (
    student_id INT AUTO_INCREMENT PRIMARY KEY,
    student_name VARCHAR(50) NOT NULL,
    age INT,
    gender ENUM('男', '女')
);

CREATE TABLE teachers (
    teacher_id INT AUTO_INCREMENT PRIMARY KEY,
    teacher_name VARCHAR(50) NOT NULL,
    subject VARCHAR(50)
);

CREATE TABLE course_selection (
    selection_id INT AUTO_INCREMENT PRIMARY KEY,
    student_id INT,
    course_id INT,
    FOREIGN KEY (student_id) REFERENCES students(student_id),
    FOREIGN KEY (course_id) REFERENCES courses(course_id)
);

CREATE TABLE scores (
    score_id INT AUTO_INCREMENT PRIMARY KEY,
    student_id INT,
    course_id INT,
    score DECIMAL(5, 2),
    FOREIGN KEY (student_id) REFERENCES students(student_id),
    FOREIGN KEY (course_id) REFERENCES courses(course_id)
);

INSERT INTO students (student_name, age, gender)
VALUES
    ('李四', 20, '男'),
    ('王五', 21, '女');

INSERT INTO courses (course_name, course_description)
VALUES
    ('数学', '基础数学课程'),
    ('英语', '英语语言学习课程'); 

INSERT INTO teachers (teacher_name, subject)
VALUES
    ('赵老师', '数学'),
    ('钱老师', '英语');

INSERT INTO course_selection (student_id, course_id)
VALUES
    (1, 1),
    (1, 2),
    (2, 1);     

INSERT INTO scores (student_id, course_id, score)
VALUES
    (1, 1, 85.5),
    (1, 2, 90.0),
    (2, 1, 88.0);