mysql建表规范

-- 创建一个规范化的用户表
CREATE TABLE users (
    user_id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL UNIQUE,
    email VARCHAR(100) NOT NULL UNIQUE,
    password_hash CHAR(64) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

-- 为用户表的username字段创建索引
CREATE INDEX idx_username ON users(username);

-- 创建一个分区表
CREATE TABLE orders (
    order_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    order_date DATE NOT NULL,
    total_amount DECIMAL(10, 2) NOT NULL,
    INDEX idx_user_id (user_id)
) PARTITION BY RANGE (YEAR(order_date)) (
    PARTITION p0 VALUES LESS THAN (2010),
    PARTITION p1 VALUES LESS THAN (2020),
    PARTITION p2 VALUES LESS THAN MAXVALUE
);