Assume the connection to database is saved in connection.php file. The php syntax to connect to the database.

Here is a basic example of how you can connect to a database using PHP:

1. First, you need to include the connection.php file in your PHP script. You can do this using the include statement:

include 'connection.php';

2. In your connection.php file, you should have something like this:

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection
if ($conn->connect_error) {
  die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully";
?>

In this example, replace "localhost", "username", "password", and "myDB" with your actual database host, username, password, and database name.

3. Now, you can use the $conn object to interact with your database. For example, to run a SQL query:

$sql = "SELECT id, firstname, lastname FROM MyGuests";
$result = $conn->query($sql);

4. Don't forget to close the connection when you're done:

$conn->close();

Remember to handle errors and secure your database credentials properly in your actual code.