How does php connect to the database?

PHP has two methods to connect to the mysql database: mysqli and pdo.

The first method: use mysqli to connect to the mysql database

The code example is as follows

<?php
$host=&#39;127.0.0.1&#39;;
$user=&#39;root&#39;;
$password=&#39;root&#39;;
$dbName=&#39;php&#39;;
$link=new mysqli($host,$user,$password,$dbName);
if ($link->connect_error){
    die("连接失败：".$link->connect_error);
}
    $sql="select * from admins";
    $res=$link->query($sql);
    $data=$res->fetch_all();
    var_dump($data);

The second method: use PDO to connect to the database

The code example is as follows :

<?php
$host=&#39;127.0.0.1&#39;;
$user=&#39;root&#39;;
$password=&#39;root&#39;;
$dbName=&#39;php&#39;;
$pdo=new PDO("mysql:host=$host;dbname=$dbName",$user,$password);
$sql="select * from admins";
$data=$pdo->query($sql)->fetch();
var_dump($data);

The above is the detailed content of How does php connect to the database?. For more information, please follow other related articles on the PHP Chinese website!