If you need to connect to a mysql database from php you can do it like this:
$DBH = ‘localhost’;
$DBU = ‘root’;
$DBPWD = ‘password’;
$DBN = ‘petstore’;
$conn = mysql_connect($DBH, $DBU, $DBPWD) or die (“Error: Could not connect to database.”);
This allows you to make a connection to the mysql database and gets it ready for you to make queries and manipulate the data.