MySQL分库分表（无中间件）

Tue, 23 Apr 2024 20:46:01 +0800

MySQL分库分表（无中间件）

一、分库分表方案设计

1. 垂直拆分 (按业务模块)

 1-- 原始单体数据库
 2CREATE DATABASE ecommerce;
 3USE ecommerce;
 4
 5-- 垂直拆分后的数据库
 6-- 用户库
 7CREATE DATABASE user_center;
 8USE user_center;
 9
10CREATE TABLE users (
11 user_id BIGINT PRIMARY KEY,
12 username VARCHAR(50) UNIQUE,
13 email VARCHAR(100) UNIQUE,
14 password VARCHAR(100),
15 mobile VARCHAR(20),
16 status TINYINT DEFAULT 1,
17 created_at DATETIME,
18 updated_at DATETIME
19);
20
21CREATE TABLE user_profiles (
22 user_id BIGINT PRIMARY KEY,
23 real_name VARCHAR(50),
24 avatar VARCHAR(200),
25 gender TINYINT,
26 birthday DATE,
27 bio TEXT
28);
29
30CREATE TABLE user_address (
31 address_id BIGINT PRIMARY KEY,
32 user_id BIGINT,
33 province VARCHAR(50),
34 city VARCHAR(50),
35 district VARCHAR(50),
36 detail VARCHAR(200),
37 is_default TINYINT DEFAULT 0,
38 INDEX idx_user_id (user_id)
39);
40
41-- 订单库
42CREATE DATABASE order_center;
43USE order_center;
44
45CREATE TABLE orders (
46 order_id BIGINT PRIMARY KEY,
47 user_id BIGINT,
48 total_amount DECIMAL(10,2),
49 status TINYINT,
50 payment_status TINYINT,
51 created_at DATETIME,
52 paid_at DATETIME
53);
54
55CREATE TABLE order_items (
56 item_id BIGINT PRIMARY KEY,
57 order_id BIGINT,
58 product_id BIGINT,
59 product_name VARCHAR(100),
60 price DECIMAL(10,2),
61 quantity INT,
62 INDEX idx_order_id (order_id)
63);
64
65-- 商品库
66CREATE DATABASE product_center;
67USE product_center;
68
69CREATE TABLE products (
70 product_id BIGINT PRIMARY KEY,
71 name VARCHAR(100),
72 category_id INT,
73 price DECIMAL(10,2),
74 stock INT,
75 status TINYINT,
76 created_at DATETIME
77);
78
79CREATE TABLE categories (
80 category_id INT PRIMARY KEY,
81 name VARCHAR(50),
82 parent_id INT
83);

2. 水平拆分（按数据量）

用户表水平分表（10个分表）

 1-- 在 user_center 数据库中创建分表
 2USE user_center;
 3
 4-- 下面语句中的//为分隔符
 5DELIMITER //
 6CREATE PROCEDURE CreateUserShards()
 7BEGIN
 8 DECLARE i INT DEFAULT 0;
 9 WHILE i < 10 DO
10 SET @sql = CONCAT('
11 CREATE TABLE users_', i, ' (
12 user_id BIGINT PRIMARY KEY,
13 username VARCHAR(50) NOT NULL,
14 email VARCHAR(100),
15 password VARCHAR(100),
16 mobile VARCHAR(20),
17 status TINYINT DEFAULT 1,
18 created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
19 updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
20 UNIQUE KEY uk_username_', i, ' (username),
21 UNIQUE KEY uk_email_', i, ' (email),
22 INDEX idx_mobile_', i, ' (mobile),
23 INDEX idx_created_', i, ' (created_at)
24 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
25 ');
26 PREPARE stmt FROM @sql;
27 EXECUTE stmt;
28 DEALLOCATE PREPARE stmt;
29 SET i = i + 1;
30 END WHILE;
31END//
32DELIMITER ;
33
34CALL CreateUserShards();

订单表水平分表（按用户ID分表）

 1USE order_center;
 2
 3DELIMITER //
 4CREATE PROCEDURE CreateOrderShards()
 5BEGIN
 6 DECLARE i INT DEFAULT 0;
 7 WHILE i < 10 DO
 8 SET @sql = CONCAT('
 9 CREATE TABLE orders_', i, ' (
10 order_id BIGINT PRIMARY KEY,
11 user_id BIGINT NOT NULL,
12 total_amount DECIMAL(10,2),
13 status TINYINT DEFAULT 1,
14 payment_status TINYINT DEFAULT 0,
15 created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
16 paid_at DATETIME,
17 INDEX idx_user_id_', i, ' (user_id),
18 INDEX idx_created_', i, ' (created_at),
19 INDEX idx_status_', i, ' (status)
20 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
21 ');
22 PREPARE stmt FROM @sql;
23 EXECUTE stmt;
24 DEALLOCATE PREPARE stmt;
25 
26 -- 创建对应的订单项分表
27 SET @sql = CONCAT('
28 CREATE TABLE order_items_', i, ' (
29 item_id BIGINT PRIMARY KEY,
30 order_id BIGINT NOT NULL,
31 product_id BIGINT,
32 product_name VARCHAR(100),
33 price DECIMAL(10,2),
34 quantity INT,
35 INDEX idx_order_id_', i, ' (order_id),
36 INDEX idx_product_id_', i, ' (product_id)
37 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
38 ');
39 PREPARE stmt FROM @sql;
40 EXECUTE stmt;
41 DEALLOCATE PREPARE stmt;
42 
43 SET i = i + 1;
44 END WHILE;
45END//
46DELIMITER ;
47
48CALL CreateOrderShards();

二、程序中处理（PHP）

1. 基础配置类

 1<?php
 2// Config.php
 3class Config {
 4 private static $instance;
 5 private $config;
 6 
 7 private function __construct() {
 8 $this->config = [
 9 'databases' => [
10 'user_center' => [
11 'host' => 'localhost',
12 'port' => 3306,
13 'username' => 'root',
14 'password' => 'password',
15 'dbname' => 'user_center'
16 ],
17 'order_center' => [
18 'host' => 'localhost',
19 'port' => 3306,
20 'username' => 'root',
21 'password' => 'password',
22 'dbname' => 'order_center'
23 ],
24 'product_center' => [
25 'host' => 'localhost',
26 'port' => 3306,
27 'username' => 'root',
28 'password' => 'password',
29 'dbname' => 'product_center'
30 ]
31 ],
32 'shard' => [
33 'user' => 10, // 用户表10个分片
34 'order' => 10 // 订单表10个分片
35 ]
36 ];
37 }
38 
39 public static function getInstance() {
40 if (!self::$instance) {
41 self::$instance = new self();
42 }
43 return self::$instance;
44 }
45 
46 public function get($key) {
47 $keys = explode('.', $key);
48 $value = $this->config;
49 
50 foreach ($keys as $k) {
51 if (!isset($value[$k])) {
52 return null;
53 }
54 $value = $value[$k];
55 }
56 
57 return $value;
58 }
59}

2. 分片路由类

 1<?php
 2// ShardRouter.php
 3class ShardRouter {
 4 private $shardConfig;
 5 
 6 public function __construct() {
 7 $config = Config::getInstance();
 8 $this->shardConfig = $config->get('shard');
 9 }
10 
11 /**
12 * 根据用户ID计算分片
13 */
14 public function getUserShard($userId) {
15 return $userId % $this->shardConfig['user'];
16 }
17 
18 /**
19 * 根据订单ID计算分片（订单按用户ID分片）
20 */
21 public function getOrderShard($orderId) {
22 // 假设订单ID包含用户ID信息
23 $userId = $this->extractUserIdFromOrderId($orderId);
24 return $userId % $this->shardConfig['order'];
25 }
26 
27 /**
28 * 根据用户名计算分片（用于登录查询）
29 */
30 public function getShardByString($str, $type = 'user') {
31 $shardCount = $this->shardConfig[$type];
32 return crc32($str) % $shardCount;
33 }
34 
35 /**
36 * 生成分布式ID（雪花算法）
37 */
38 public function generateId($shardId = 0, $timestamp = null) {
39 $timestamp = $timestamp ?? (int)(microtime(true) * 1000);
40 $workerId = $shardId % 1024;
41 $sequence = mt_rand(0, 4095);
42 
43 return (($timestamp - 1577836800000) << 22) 
44 | ($workerId << 12) 
45 | $sequence;
46 }
47 
48 /**
49 * 从订单ID提取用户ID（根据业务规则）
50 */
51 private function extractUserIdFromOrderId($orderId) {
52 // 实际业务中需要根据ID生成规则来解析
53 // 这里简单返回订单ID的低位部分作为用户ID
54 return $orderId & 0x3FFFFFFF;
55 }
56 
57 /**
58 * 获取表名
59 */
60 public function getTableName($baseTable, $shardId) {
61 return $baseTable . '_' . $shardId;
62 }
63}

3. 数据库连接管理

 1<?php
 2// DatabaseManager.php
 3class DatabaseManager {
 4 private static $instance;
 5 private $connections = [];
 6 private $config;
 7 
 8 private function __construct() {
 9 $this->config = Config::getInstance();
10 }
11 
12 public static function getInstance() {
13 if (!self::$instance) {
14 self::$instance = new self();
15 }
16 return self::$instance;
17 }
18 
19 /**
20 * 获取数据库连接
21 */
22 public function getConnection($database, $shardId = null) {
23 $key = $database . ($shardId !== null ? '_' . $shardId : '');
24 
25 if (!isset($this->connections[$key])) {
26 $dbConfig = $this->config->get("databases.{$database}");
27 
28 if (!$dbConfig) {
29 throw new Exception("Database config not found: {$database}");
30 }
31 
32 try {
33 $dsn = "mysql:host={$dbConfig['host']};port={$dbConfig['port']};dbname={$dbConfig['dbname']};charset=utf8mb4";
34 
35 $this->connections[$key] = new PDO(
36 $dsn,
37 $dbConfig['username'],
38 $dbConfig['password'],
39 [
40 PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
41 PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
42 PDO::ATTR_EMULATE_PREPARES => false,
43 PDO::ATTR_PERSISTENT => false
44 ]
45 );
46 } catch (PDOException $e) {
47 throw new Exception("Database connection failed: " . $e->getMessage());
48 }
49 }
50 
51 return $this->connections[$key];
52 }
53 
54 /**
55 * 开始事务（单分片事务）
56 */
57 public function beginTransaction($database, $shardId = null) {
58 $connection = $this->getConnection($database, $shardId);
59 return $connection->beginTransaction();
60 }
61 
62 /**
63 * 提交事务
64 */
65 public function commit($database, $shardId = null) {
66 $connection = $this->getConnection($database, $shardId);
67 return $connection->commit();
68 }
69 
70 /**
71 * 回滚事务
72 */
73 public function rollback($database, $shardId = null) {
74 $connection = $this->getConnection($database, $shardId);
75 return $connection->rollback();
76 }
77}

4. 用户服务类示例（完整CRUD）

 1<?php
 2// UserService.php
 3class UserService {
 4 private $db;
 5 private $router;
 6 
 7 public function __construct() {
 8 $this->db = DatabaseManager::getInstance();
 9 $this->router = new ShardRouter();
 10 }
 11 
 12 /**
 13 * 创建用户（写入操作）
 14 */
 15 public function createUser($userData) {
 16 // 生成用户ID
 17 $userId = $this->router->generateId();
 18 $shardId = $this->router->getUserShard($userId);
 19 
 20 $tableName = $this->router->getTableName('users', $shardId);
 21 $connection = $this->db->getConnection('user_center', $shardId);
 22 
 23 try {
 24 // 开始事务
 25 $this->db->beginTransaction('user_center', $shardId);
 26 
 27 // 插入用户基础信息
 28 $sql = "INSERT INTO {$tableName} 
 29 (user_id, username, email, password, mobile, created_at) 
 30 VALUES (?, ?, ?, ?, ?, NOW())";
 31 
 32 $stmt = $connection->prepare($sql);
 33 $stmt->execute([
 34 $userId,
 35 $userData['username'],
 36 $userData['email'],
 37 password_hash($userData['password'], PASSWORD_DEFAULT),
 38 $userData['mobile'] ?? null
 39 ]);
 40 
 41 // 插入用户档案（垂直分库，但在同一个事务中）
 42 $this->createUserProfile($userId, $userData);
 43 
 44 // 提交事务
 45 $this->db->commit('user_center', $shardId);
 46 
 47 return $userId;
 48 
 49 } catch (Exception $e) {
 50 $this->db->rollback('user_center', $shardId);
 51 throw new Exception("创建用户失败: " . $e->getMessage());
 52 }
 53 }
 54 
 55 /**
 56 * 更新用户信息
 57 */
 58 public function updateUser($userId, $updateData) {
 59 $shardId = $this->router->getUserShard($userId);
 60 $tableName = $this->router->getTableName('users', $shardId);
 61 $connection = $this->db->getConnection('user_center', $shardId);
 62 
 63 $allowedFields = ['email', 'mobile', 'password'];
 64 $setParts = [];
 65 $params = [];
 66 
 67 foreach ($updateData as $field => $value) {
 68 if (in_array($field, $allowedFields)) {
 69 if ($field === 'password') {
 70 $value = password_hash($value, PASSWORD_DEFAULT);
 71 }
 72 $setParts[] = "{$field} = ?";
 73 $params[] = $value;
 74 }
 75 }
 76 
 77 if (empty($setParts)) {
 78 throw new Exception("没有有效的更新字段");
 79 }
 80 
 81 $params[] = $userId;
 82 
 83 $sql = "UPDATE {$tableName} SET " . implode(', ', $setParts) . " WHERE user_id = ?";
 84 $stmt = $connection->prepare($sql);
 85 
 86 return $stmt->execute($params);
 87 }
 88 
 89 /**
 90 * 根据用户ID查询（精确查询）
 91 */
 92 public function getUserById($userId) {
 93 $shardId = $this->router->getUserShard($userId);
 94 $tableName = $this->router->getTableName('users', $shardId);
 95 $connection = $this->db->getConnection('user_center', $shardId);
 96 
 97 $sql = "SELECT * FROM {$tableName} WHERE user_id = ?";
 98 $stmt = $connection->prepare($sql);
 99 $stmt->execute([$userId]);
100 
101 $user = $stmt->fetch();
102 if ($user) {
103 $user['profile'] = $this->getUserProfile($userId);
104 $user['addresses'] = $this->getUserAddresses($userId);
105 }
106 
107 return $user;
108 }
109 
110 /**
111 * 根据用户名查询（需要计算分片）
112 */
113 public function getUserByUsername($username) {
114 $shardId = $this->router->getShardByString($username, 'user');
115 $tableName = $this->router->getTableName('users', $shardId);
116 $connection = $this->db->getConnection('user_center', $shardId);
117 
118 $sql = "SELECT * FROM {$tableName} WHERE username = ?";
119 $stmt = $connection->prepare($sql);
120 $stmt->execute([$username]);
121 
122 return $stmt->fetch();
123 }
124 
125 /**
126 * 批量查询用户信息
127 */
128 public function getUsersByIds($userIds) {
129 $usersByShard = [];
130 
131 // 按分片分组用户ID
132 foreach ($userIds as $userId) {
133 $shardId = $this->router->getUserShard($userId);
134 $usersByShard[$shardId][] = $userId;
135 }
136 
137 $results = [];
138 foreach ($usersByShard as $shardId => $shardUserIds) {
139 $tableName = $this->router->getTableName('users', $shardId);
140 $connection = $this->db->getConnection('user_center', $shardId);
141 
142 $placeholders = str_repeat('?,', count($shardUserIds) - 1) . '?';
143 $sql = "SELECT * FROM {$tableName} WHERE user_id IN ({$placeholders})";
144 
145 $stmt = $connection->prepare($sql);
146 $stmt->execute($shardUserIds);
147 
148 $results = array_merge($results, $stmt->fetchAll());
149 }
150 
151 return $results;
152 }
153 
154 /**
155 * 复杂查询：按条件搜索用户（需要遍历分片）
156 */
157 public function searchUsers($conditions, $page = 1, $pageSize = 20) {
158 $allUsers = [];
159 $shardCount = Config::getInstance()->get('shard.user');
160 
161 for ($shardId = 0; $shardId < $shardCount; $shardId++) {
162 $tableName = $this->router->getTableName('users', $shardId);
163 $connection = $this->db->getConnection('user_center', $shardId);
164 
165 $where = [];
166 $params = [];
167 
168 if (!empty($conditions['username'])) {
169 $where[] = "username LIKE ?";
170 $params[] = $conditions['username'] . '%';
171 }
172 
173 if (!empty($conditions['email'])) {
174 $where[] = "email LIKE ?";
175 $params[] = $conditions['email'] . '%';
176 }
177 
178 if (!empty($conditions['mobile'])) {
179 $where[] = "mobile LIKE ?";
180 $params[] = $conditions['mobile'] . '%';
181 }
182 
183 $whereClause = $where ? "WHERE " . implode(' AND ', $where) : "";
184 $offset = ($page - 1) * $pageSize;
185 
186 $sql = "SELECT * FROM {$tableName} {$whereClause} LIMIT ? OFFSET ?";
187 $params[] = $pageSize;
188 $params[] = $offset;
189 
190 $stmt = $connection->prepare($sql);
191 $stmt->execute($params);
192 
193 $shardUsers = $stmt->fetchAll();
194 $allUsers = array_merge($allUsers, $shardUsers);
195 }
196 
197 // 在PHP中进行排序和分页
198 usort($allUsers, function($a, $b) {
199 return strcmp($b['created_at'], $a['created_at']);
200 });
201 
202 return array_slice($allUsers, 0, $pageSize);
203 }
204 
205 /**
206 * 删除用户
207 */
208 public function deleteUser($userId) {
209 $shardId = $this->router->getUserShard($userId);
210 $tableName = $this->router->getTableName('users', $shardId);
211 $connection = $this->db->getConnection('user_center', $shardId);
212 
213 try {
214 $this->db->beginTransaction('user_center', $shardId);
215 
216 // 删除用户基础信息
217 $sql = "DELETE FROM {$tableName} WHERE user_id = ?";
218 $stmt = $connection->prepare($sql);
219 $stmt->execute([$userId]);
220 
221 // 删除关联数据
222 $this->deleteUserProfile($userId);
223 $this->deleteUserAddresses($userId);
224 
225 $this->db->commit('user_center', $shardId);
226 return true;
227 
228 } catch (Exception $e) {
229 $this->db->rollback('user_center', $shardId);
230 throw new Exception("删除用户失败: " . $e->getMessage());
231 }
232 }
233 
234 // 用户档案相关方法
235 private function createUserProfile($userId, $userData) {
236 $connection = $this->db->getConnection('user_center');
237 
238 $sql = "INSERT INTO user_profiles 
239 (user_id, real_name, avatar, gender, birthday, bio) 
240 VALUES (?, ?, ?, ?, ?, ?)";
241 
242 $stmt = $connection->prepare($sql);
243 return $stmt->execute([
244 $userId,
245 $userData['real_name'] ?? '',
246 $userData['avatar'] ?? '',
247 $userData['gender'] ?? 0,
248 $userData['birthday'] ?? null,
249 $userData['bio'] ?? ''
250 ]);
251 }
252 
253 private function getUserProfile($userId) {
254 $connection = $this->db->getConnection('user_center');
255 
256 $sql = "SELECT * FROM user_profiles WHERE user_id = ?";
257 $stmt = $connection->prepare($sql);
258 $stmt->execute([$userId]);
259 
260 return $stmt->fetch();
261 }
262 
263 private function getUserAddresses($userId) {
264 $connection = $this->db->getConnection('user_center');
265 
266 $sql = "SELECT * FROM user_address WHERE user_id = ? ORDER BY is_default DESC";
267 $stmt = $connection->prepare($sql);
268 $stmt->execute([$userId]);
269 
270 return $stmt->fetchAll();
271 }
272 
273 private function deleteUserProfile($userId) {
274 $connection = $this->db->getConnection('user_center');
275 
276 $sql = "DELETE FROM user_profiles WHERE user_id = ?";
277 $stmt = $connection->prepare($sql);
278 return $stmt->execute([$userId]);
279 }
280 
281 private function deleteUserAddresses($userId) {
282 $connection = $this->db->getConnection('user_center');
283 
284 $sql = "DELETE FROM user_address WHERE user_id = ?";
285 $stmt = $connection->prepare($sql);
286 return $stmt->execute([$userId]);
287 }
288}

5. 订单服务类示例

 1<?php
 2// OrderService.php
 3class OrderService {
 4 private $db;
 5 private $router;
 6 
 7 public function __construct() {
 8 $this->db = DatabaseManager::getInstance();
 9 $this->router = new ShardRouter();
 10 }
 11 
 12 /**
 13 * 创建订单
 14 */
 15 public function createOrder($orderData) {
 16 $userId = $orderData['user_id'];
 17 $shardId = $this->router->getUserShard($userId);
 18 
 19 $orderId = $this->router->generateId($shardId);
 20 $orderTable = $this->router->getTableName('orders', $shardId);
 21 $itemTable = $this->router->getTableName('order_items', $shardId);
 22 $connection = $this->db->getConnection('order_center', $shardId);
 23 
 24 try {
 25 $this->db->beginTransaction('order_center', $shardId);
 26 
 27 // 插入订单主表
 28 $sql = "INSERT INTO {$orderTable} 
 29 (order_id, user_id, total_amount, status, payment_status, created_at) 
 30 VALUES (?, ?, ?, 1, 0, NOW())";
 31 
 32 $stmt = $connection->prepare($sql);
 33 $stmt->execute([
 34 $orderId,
 35 $userId,
 36 $orderData['total_amount']
 37 ]);
 38 
 39 // 插入订单项
 40 foreach ($orderData['items'] as $item) {
 41 $itemId = $this->router->generateId($shardId);
 42 
 43 $sql = "INSERT INTO {$itemTable} 
 44 (item_id, order_id, product_id, product_name, price, quantity) 
 45 VALUES (?, ?, ?, ?, ?, ?)";
 46 
 47 $stmt = $connection->prepare($sql);
 48 $stmt->execute([
 49 $itemId,
 50 $orderId,
 51 $item['product_id'],
 52 $item['product_name'],
 53 $item['price'],
 54 $item['quantity']
 55 ]);
 56 }
 57 
 58 $this->db->commit('order_center', $shardId);
 59 return $orderId;
 60 
 61 } catch (Exception $e) {
 62 $this->db->rollback('order_center', $shardId);
 63 throw new Exception("创建订单失败: " . $e->getMessage());
 64 }
 65 }
 66 
 67 /**
 68 * 更新订单状态
 69 */
 70 public function updateOrderStatus($orderId, $status) {
 71 $shardId = $this->router->getOrderShard($orderId);
 72 $tableName = $this->router->getTableName('orders', $shardId);
 73 $connection = $this->db->getConnection('order_center', $shardId);
 74 
 75 $sql = "UPDATE {$tableName} SET status = ?, updated_at = NOW() WHERE order_id = ?";
 76 $stmt = $connection->prepare($sql);
 77 
 78 return $stmt->execute([$status, $orderId]);
 79 }
 80 
 81 /**
 82 * 根据订单ID查询
 83 */
 84 public function getOrderById($orderId) {
 85 $shardId = $this->router->getOrderShard($orderId);
 86 $orderTable = $this->router->getTableName('orders', $shardId);
 87 $itemTable = $this->router->getTableName('order_items', $shardId);
 88 $connection = $this->db->getConnection('order_center', $shardId);
 89 
 90 // 查询订单基本信息
 91 $sql = "SELECT * FROM {$orderTable} WHERE order_id = ?";
 92 $stmt = $connection->prepare($sql);
 93 $stmt->execute([$orderId]);
 94 
 95 $order = $stmt->fetch();
 96 if ($order) {
 97 // 查询订单项
 98 $sql = "SELECT * FROM {$itemTable} WHERE order_id = ?";
 99 $stmt = $connection->prepare($sql);
100 $stmt->execute([$orderId]);
101 $order['items'] = $stmt->fetchAll();
102 }
103 
104 return $order;
105 }
106 
107 /**
108 * 查询用户订单列表
109 */
110 public function getUserOrders($userId, $page = 1, $pageSize = 20) {
111 $shardId = $this->router->getUserShard($userId);
112 $tableName = $this->router->getTableName('orders', $shardId);
113 $connection = $this->db->getConnection('order_center', $shardId);
114 
115 $offset = ($page - 1) * $pageSize;
116 
117 $sql = "SELECT * FROM {$tableName} 
118 WHERE user_id = ? 
119 ORDER BY created_at DESC 
120 LIMIT ? OFFSET ?";
121 
122 $stmt = $connection->prepare($sql);
123 $stmt->execute([$userId, $pageSize, $offset]);
124 
125 return $stmt->fetchAll();
126 }
127}

6. 使用示例

6.1 用户注册和订单创建

 1<?php
 2// register_and_order.php
 3require_once 'Config.php';
 4require_once 'ShardRouter.php';
 5require_once 'DatabaseManager.php';
 6require_once 'UserService.php';
 7require_once 'OrderService.php';
 8
 9try {
10 // 初始化服务
11 $userService = new UserService();
12 $orderService = new OrderService();
13 
14 // 1. 创建用户
15 $userData = [
16 'username' => 'zhangsan',
17 'email' => 'zhangsan@example.com',
18 'password' => '123456',
19 'mobile' => '13800138000',
20 'real_name' => '张三',
21 'avatar' => 'avatar.jpg'
22 ];
23 
24 $userId = $userService->createUser($userData);
25 echo "用户创建成功，ID: {$userId}\n";
26 
27 // 2. 为用户创建订单
28 $orderData = [
29 'user_id' => $userId,
30 'total_amount' => 299.00,
31 'items' => [
32 [
33 'product_id' => 1001,
34 'product_name' => 'iPhone 14',
35 'price' => 299.00,
36 'quantity' => 1
37 ]
38 ]
39 ];
40 
41 $orderId = $orderService->createOrder($orderData);
42 echo "订单创建成功，ID: {$orderId}\n";
43 
44 // 3. 查询用户信息
45 $user = $userService->getUserById($userId);
46 echo "用户信息: " . json_encode($user, JSON_UNESCAPED_UNICODE) . "\n";
47 
48 // 4. 查询订单信息
49 $order = $orderService->getOrderById($orderId);
50 echo "订单信息: " . json_encode($order, JSON_UNESCAPED_UNICODE) . "\n";
51 
52 // 5. 查询用户订单列表
53 $orders = $orderService->getUserOrders($userId);
54 echo "用户订单数量: " . count($orders) . "\n";
55 
56} catch (Exception $e) {
57 echo "操作失败: " . $e->getMessage() . "\n";
58}

6.2 批量操作示例

 1<?php
 2// batch_operations.php
 3require_once 'UserService.php';
 4
 5$userService = new UserService();
 6
 7// 批量查询用户信息
 8$userIds = [123456, 234567, 345678, 456789];
 9$users = $userService->getUsersByIds($userIds);
10echo "批量查询到 " . count($users) . " 个用户\n";
11
12// 复杂搜索
13$conditions = [
14 'username' => 'zhang',
15 'mobile' => '138'
16];
17$users = $userService->searchUsers($conditions, 1, 10);
18echo "搜索到 " . count($users) . " 个用户\n";
19
20// 更新用户信息
21$updateResult = $userService->updateUser(123456, [
22 'email' => 'new_email@example.com',
23 'mobile' => '13900139000'
24]);
25echo "更新结果: " . ($updateResult ? '成功' : '失败') . "\n";

三、总结

写入操作：

先计算分片：根据分片键（如用户ID）计算目标分片

分库分表 on Leanku 的博客

MySQL分库分表（无中间件）

MySQL分库分表（无中间件）

一、 分库分表方案设计

1. 垂直拆分 (按业务模块)

2. 水平拆分 （按数据量）

用户表水平分表（10个分表）

订单表水平分表（按用户ID分表）

二、程序中处理（PHP）

1. 基础配置类

2. 分片路由类

3. 数据库连接管理

4. 用户服务类示例（完整CRUD）

5. 订单服务类示例

6. 使用示例

6.1 用户注册和订单创建

6.2 批量操作示例

三、 总结

写入操作：

一、分库分表方案设计

2. 水平拆分（按数据量）

三、总结