最簡單 Java 論壇數據庫設計：三張核心表結構

表結構

-- 用戶表
CREATE TABLE users (
    user_id INT PRIMARY KEY AUTO_INCREMENT,
    username VARCHAR(50) UNIQUE NOT NULL,
    password_hash VARCHAR(100) NOT NULL,
    email VARCHAR(100),
    reg_time DATETIME DEFAULT CURRENT_TIMESTAMP
);

-- 主題/帖子表
CREATE TABLE topics (
    topic_id INT PRIMARY KEY AUTO_INCREMENT,
    title VARCHAR(200) NOT NULL,
    content TEXT NOT NULL,
    author_id INT NOT NULL,
    post_time DATETIME DEFAULT CURRENT_TIMESTAMP,
    view_count INT DEFAULT 0,
    FOREIGN KEY (author_id) REFERENCES users(user_id)
);

-- 回復表
CREATE TABLE replies (
    reply_id INT PRIMARY KEY AUTO_INCREMENT,
    topic_id INT NOT NULL,
    content TEXT NOT NULL,
    author_id INT NOT NULL,
    reply_time DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (topic_id) REFERENCES topics(topic_id),
    FOREIGN KEY (author_id) REFERENCES users(user_id)
);

擴展建議

• 分類表 `categories`，`topics` 加 `category_id`。
• 版塊/權限表、積分表、私信表。
• 索引：`topics(author_id)`、`replies(topic_id, reply_time)`、`users(username)`。