Question

$servername1 = "localhost1";
$username1 = "user1";
$password1 = "pwd";
$dbname1 = "dbs1";
$servername2 = "localhost2";
$username2 = "user2";
$password2 = "ped2";
$dbname2 = "dbs2";
// Create connection
$conn = new mysqli($servername1, $username1, $password1, $dbname1);
// Check connection
if ($conn->connect_error) {
    $conn = new mysqli($servername2, $username2, $password2, $dbname2);
    if ($conn->connect_error) {
            die("Connection failed: " . $conn->connect_error);}

}

可以实现这种类型的连接吗？当我故意在第一个数据库凭据中实现此错误时，我收到一条警告未知MySQL服务器主机＆＃39; localhost1＆＃39; 并且不会加载页面。为什么这不起作用？

Answer 1

您应该使用“localhost”或IP地址连接到SQL Server。在您的情况下，它尝试连接到不存在的“localhost1”（如在您的变量中）（除非您更改了主机文件）。尝试使用IP（127.0.0.1用于localhost，其他任何用于备份）

干杯， JCK

Answer 2

您可以先尝试Ping。

OR

if ($mysqli->connect_errno) {
echo "Failed to connect to MySQL: (" . $mysqli->connect_errno . ") 
" .    $mysqli->connect_error;
}

OR

extension_loaded("mysql");

Answer 3

我创建了一个数据库列表，然后遍历它们并尝试连接。使用多个数据库应该没问题。无法使用localhost1和localhost2（只有localhost可能是127.0.0.1）。你应该使用IP地址。

以下是代码：

<?php
$Databases = array(
		0 => array(
			'db_kind' => 'postgres',
			'host' => $server1[$server1["current"]]["host"],
			'port' => $server1[$server1["current"]]["port"],
			'db_name' => 'database1',
			'username' => 'xxx',
			'password' => 'yyy',
			"type"=>DB_TYPE_3,
		),
		1 => array(
			'db_kind' => 'postgres',
			'host' => $server1[$server1["current"]]["host"],
			'port' => $server1[$server1["current"]]["port"],
			'db_name' => 'database2',
			'username' => 'xxx',
			'password' => 'yyy',
			"type"=>DB_TYPE_2,
		),
		2 => array(
			'db_kind' => 'postgres',
			'host' => $server1[$server1["current"]]["host"],
			'port' => $server1[$server1["current"]]["port"],
			'db_name' => 'database3',
			'username' => 'xxx',
			'password' => 'yyy',
			"type"=>DB_TYPE_1,
		),
	);
	
	for($i=0;$i<count($Databases);$i++)
	{
		if($last_db_ind>=count($Databases)){
			$last_db_ind=0;
		}
		if(($db =& db_connect($last_db_ind++))==false){
			echo 'Connection failed for DB: '. $Databases["db_name"] . ', DB              index: '.$last_db_ind;
			continue;
	}

?>

主数据库关闭时连接到备用数据库？

3 个答案: