swoole怎么连接数据库

function swoole_mysql->connect(array $serverConfig, callable $callback);

<?php
//实例化资源
$db = new swoole_mysql();
$config = [
	&#39;host&#39;=>&#39;localhost&#39;,
	&#39;user&#39;=>&#39;root&#39;,
	&#39;password&#39;=>&#39;root&#39;,
	&#39;database&#39;=>&#39;amsdata&#39;,
	&#39;charset&#39;=>&#39;utf8&#39;
];
//连接数据库
$db->connect($config,function($db,$r){
	//mysql操作
	if($r === false){
		var_dump($db->connect_errno,$db->connect_error);
		die("连接数据库失败");
	}
	$sql = &#39;show tables&#39;;
	$db->query($sql,function(swoole_mysql $db,$r){
		if($r === false){
			var_dump($db->error);
			die("操作失败");
		}
		var_dump($r[0]); //若有操作成功打印取出数据的第一个数组元素
		$db->close();
	});
});