private function getDbSize() {
//include(APPPATH.'config/database.php');
$sql = "SHOW TABLE STATUS FROM " . $db['default']['database'];
$result=$this->mysqli->query($sql);
$size = 0;
foreach($result->result_array() as $row){
$size += $row["Data_length"] + $row["Index_length"];
}
return $size;
}