def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def values(cls, dataset, dim, expanded=True, flat=True, compute=True,
               keep_index=False):
        dim = dataset.get_dimension(dim, strict=True)
        data = dataset.data[dim.name]
        if not expanded:
            data = data.unique()
            return data.values_host if compute else data.values
        elif keep_index:
            return data
        elif compute:
            return data.values_host
        try:
            return data.values
        except Exception:
            return data.values_host