Contar registros totales de todas las db

[Nano_]

Saludos

Has intentado realizarlo por separado?

Código PHP:

$sql_world1=mysql_query("SELECT COUNT(*) as total FROM world1.online") or die (mysql_error());
$row_world1=mysql_fetch_array($sql_world1);
$total1=$row_world1['total'];
$sql_world2=mysql_query("SELECT COUNT(*) as total FROM world2.online") or die (mysql_error());
$row_world2=mysql_fetch_array($sql_world2);
$total2=$row_world2['total'];
 
 
$sql_world3=mysql_query("SELECT COUNT(*) as total FROM world3.online") or die (mysql_error());
$row_world3=mysql_fetch_array($sql_world3);
$total3=$row_world3['total'];
 
$totalGeneral=$total1+$total2+$total3;