this code setsup PDO connection of php with mysql. for running it use command :

php_mysql.php

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

try {
    $conn = new PDO("mysql:host=$servername;dbname=testdb1", $username, $password);
    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    echo "Connected successfully"; 
    }
catch(PDOException $e)
    {
    echo "Connection failed: " . $e->getMessage();
    }
?>