<?php error_reporting(E_ALL); mysql_connect('dbhost', 'username', 'password'); $db_list = mysql_list_dbs(); $i = 0; $cnt = mysql_num_rows($db_list); while ($i < $cnt) { echo mysql_db_name($db_list, $i) . "\n"; $i++; } ?>
mysql_select_db($db) or die ('Erreur :'.mysql_error());
ça serait plutot : $existe=mysql_select_db($db)