database connection info (DRY)

<?php
    // the database credentials and connection are stored in this file and included in each php page

    // db connection credentials
    $db_user="imageuser";
    $db_pass="password";
    $db_host="localhost";
    $db_name="images";

    $conn= mysqli_connect($db_host, $db_user, $db_pass, $db_name);
    if($conn->connect_errno)
    {
      // if there is a connection error, print the error
      printf("Connect failed: %s\n", $conn->connect_error);

      // handle the error or even die, why continue if there is no db connection.
      die();
    }
    ?>