$db1 = mysql_connect($hostname, $username, $password);
$db2 = mysql_connect($hostname, $username, $password, true);
mysql_select_db('database1', $db1);
mysql_select_db('database2', $db2);
//Then to query database 1, do this:
mysql_query('select * from tablename', $db1);
//and for database 2:
mysql_query('select * from tablename', $db2);
