传统开发流程：
  需求 → 设计 → 编码 → 调试 → 部署（周级）

Vibe Coding 流程：
  自然语言描述 → AI 生成代码 → 预览 → 微调 → 部署（分钟级）

CREATE TABLE users (
    id BIGSERIAL PRIMARY KEY,
    username TEXT UNIQUE NOT NULL,
    email TEXT UNIQUE NOT NULL,
    avatar_url TEXT,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE TABLE posts (
    id BIGSERIAL PRIMARY KEY,
    author_id BIGINT REFERENCES users(id),
    title TEXT NOT NULL,
    content TEXT NOT NULL,
    embedding vector(1024),
    status TEXT DEFAULT 'draft',
    published_at TIMESTAMPTZ,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE TABLE comments (
    id BIGSERIAL PRIMARY KEY,
    post_id BIGINT REFERENCES posts(id),
    user_id BIGINT REFERENCES users(id),
    content TEXT NOT NULL,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE TABLE tags (
    id SERIAL PRIMARY KEY,
    name TEXT UNIQUE NOT NULL
);

CREATE TABLE post_tags (
    post_id BIGINT REFERENCES posts(id),
    tag_id INT REFERENCES tags(id),
    PRIMARY KEY (post_id, tag_id)
);

-- 向量索引
CREATE INDEX idx_posts_embedding ON posts
USING hnsw (embedding vector_cosine_ops);