public function form_validation()
{
global $database;
$valid = new FormValidation();
$valid->validate_presences(self::$required_fields);
if (!isset($this->id)) {
$valid->unique_category();
}
// $sql="SELECT * FROM" . " ".self::$table_name."WHERE category ";
// $find_unique=$this->find_by_sql();
$valid->is_numeric('unit_price', ['min' => 0]);
return $valid;
}
