Recently, when trying to make 2 similtanious connections to the same mysql server with different databases, I noticed that this is not strictly possible without a little tweak.
The following will not work as expected:
$con1 = mysql_connect('localhost', 'user', 'pass');
mysql_select_db('db1', $con1);
$con2 = mysql_connect('localhost', 'user', 'pass');
mysql_select_db('db2', $con2);
