用mysql存储日记

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(255) NOT NULL UNIQUE,
    email VARCHAR(255) NOT NULL UNIQUE,
    password VARCHAR(255) NOT NULL
);

CREATE TABLE diaries (
    id INT AUTO_INCREMENT PRIMARY KEY,
    title VARCHAR(255) NOT NULL,
    content TEXT NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    user_id INT,
    FOREIGN KEY (user_id) REFERENCES users(id)
);

CREATE TABLE tags (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(255) NOT NULL UNIQUE
);

CREATE TABLE diary_tags (
    diary_id INT,
    tag_id INT,
    PRIMARY KEY (diary_id, tag_id),
    FOREIGN KEY (diary_id) REFERENCES diaries(id),
    FOREIGN KEY (tag_id) REFERENCES tags(id)
);

SELECT * FROM diaries WHERE user_id = ?;

SELECT d.* 
FROM diaries d 
JOIN diary_tags dt ON d.id = dt.diary_id 
JOIN tags t ON dt.tag_id = t.id 
WHERE t.name = ?;