public function add(Charge $charge)
    {
        $query = $this->_db->prepare(' INSERT INTO t_charge (
		type, dateOperation, montant, societe, designation, idProjet, created, createdBy)
		VALUES (:type, :dateOperation, :montant, :societe, :designation, :idProjet, :created, :createdBy)') or die(print_r($this->_db->errorInfo()));
        $query->bindValue(':type', $charge->type());
        $query->bindValue(':dateOperation', $charge->dateOperation());
        $query->bindValue(':montant', $charge->montant());
        $query->bindValue(':societe', $charge->societe());
        $query->bindValue(':designation', $charge->designation());
        $query->bindValue(':idProjet', $charge->idProjet());
        $query->bindValue(':created', $charge->created());
        $query->bindValue(':createdBy', $charge->createdBy());
        $query->execute();
        $query->closeCursor();
    }