php 使用mysql数据库连接池

<?php
class MySQLConnectionPool {
    private $pool = [];
    private $maxConnections = 10;
    private $dbConfig = [
        'host' => 'localhost',
        'user' => 'username',
        'password' => 'password',
        'database' => 'dbname'
    ];

    public function __construct() {
        for ($i = 0; $i < $this->maxConnections; $i++) {
            $conn = new mysqli($this->dbConfig['host'], $this->dbConfig['user'], $this->dbConfig['password'], $this->dbConfig['database']);
            if ($conn->connect_error) {
                die("连接失败: " . $conn->connect_error);
            }
            $this->pool[] = $conn;
        }
    }

    public function getConnection() {
        if (empty($this->pool)) {
            throw new Exception("没有可用的数据库连接");
        }
        return array_pop($this->pool);
    }

    public function releaseConnection($conn) {
        $this->pool[] = $conn;
    }
}

// 使用连接池
$pool = new MySQLConnectionPool();
$conn = $pool->getConnection();
$sql = "SELECT * FROM table_name";
$result = $conn->query($sql);
// 处理结果
$pool->releaseConnection($conn);
?>