mysql分表后查询语句变化

-- 原查询语句
SELECT * FROM user WHERE user_id = 123;

-- 分表后查询语句
SELECT * FROM user_0 WHERE user_id = 123;

-- 原查询语句
SELECT * FROM order WHERE order_date BETWEEN '2023-01-01' AND '2023-01-31';

-- 分表后查询语句
SELECT * FROM order_202301 WHERE order_date BETWEEN '2023-01-01' AND '2023-01-31';

$user_id = 123;
$table_name = "user_" . ($user_id % 10);
$query = "SELECT * FROM $table_name WHERE user_id = $user_id";

-- 创建分表
CREATE TABLE user_0 (
    user_id INT PRIMARY KEY,
    name VARCHAR(255),
    email VARCHAR(255)
);

CREATE TABLE user_1 (
    user_id INT PRIMARY KEY,
    name VARCHAR(255),
    email VARCHAR(255)
);

-- 插入数据
INSERT INTO user_0 (user_id, name, email) VALUES (1, 'Alice', 'alice@example.com');
INSERT INTO user_1 (user_id, name, email) VALUES (2, 'Bob', 'bob@example.com');

-- 查询数据
SELECT * FROM user_0 WHERE user_id = 1;
SELECT * FROM user_1 WHERE user_id = 2;