我将尝试在 codeigniter 中使用 pdo 连接数据库

Question

$db['default']['hostname'] ='mysql:host=myhostname;dbname=test;' ; 
$db['default']['username'] ='root';
$db['default']['password'] ='';        
$db['default']['database'] ='test';
$db['default']['dbdriver'] ='pdo';

Message: PDO::__construct(): php_network_getaddresses: getaddrinfo failed: No such host is known.

Answer 1

<?php
$hostname='localhost';
$username='root';
$password='';

try {
    $dbh = new PDO("mysql:host=$hostname;dbname=stickercollections",$username,$password);

$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
// <== add this line
echo 'Connected to Database<br/>';

$sql = "SELECT * FROM stickercollections";
foreach ($dbh->query($sql) as $row)
{
    echo $row["collection_brand"] ." - ". $row["collection_year"] ."<br/>";
}


$dbh = null;
}
catch(PDOException $e)
{
    echo $e->getMessage();
}
?> 

Answer 2

使用127.0.0.1作为您的主机名。

Answer 3

It's wrong already in your very first line....

$db['default']['hostname'] ='mysql:host=myhostname;dbname=test;' ;

['hostname'] is just 'myhostname'

The field you need is $db['default']['dsn'] = 'mysql:host=myhostname;dbname=test'

No ; here as options below will be concatenated.