mysql数据库创建关联表

-- 创建学生表
CREATE TABLE students (
    student_id INT PRIMARY KEY,
    student_name VARCHAR(100)
);

-- 创建课程表
CREATE TABLE courses (
    course_id INT PRIMARY KEY,
    course_name VARCHAR(100)
);

-- 创建关联表
CREATE TABLE student_courses (
    student_id INT,
    course_id INT,
    PRIMARY KEY (student_id, course_id),
    FOREIGN KEY (student_id) REFERENCES students(student_id),
    FOREIGN KEY (course_id) REFERENCES courses(course_id)
);

ALTER TABLE student_courses
ADD CONSTRAINT fk_student_courses_student
FOREIGN KEY (student_id) REFERENCES students(student_id);

ALTER TABLE student_courses
ADD CONSTRAINT fk_student_courses_course
FOREIGN KEY (course_id) REFERENCES courses(course_id);

CREATE INDEX idx_student_courses_student_id ON student_courses(student_id);
CREATE INDEX idx_student_courses_course_id ON student_courses(course_id);