source/core/datasystem/database/MDatabaseConnection.php
static public function getInstance($instanceName)
    {
        if (!isset(self::$instanceArray[$instanceName])) {
            self::$instanceArray[$instanceName] = new MDatabaseConnection();
        }
        return self::$instanceArray[$instanceName];
    }
static public function getInstance($instanceName)
    {
        if (!isset(self::$instanceArray[$instanceName])) {
            self::$instanceArray[$instanceName] = new MDatabaseConnection();
        }
        return self::$instanceArray[$instanceName];
    }
static public function getInstance ( $ instanceName ) { if ( ! isset ( self :: $ instanceArray [ $ instanceName ] ) ) { self :: $ instanceArray [ $ instanceName ] = new MDatabaseConnection ( ) ; } return self :: $ instanceArray [ $ instanceName ] ; }
multiton to administrate the instances of the connection
and global accessing

@param String $instanceName
@return object
multiton to administrate the instances of the connection and global accessing