Method project

dvc/compare.py:133–135

(self, *col_names: str)

        self._keys[self._keys.index(from_col_name)] = to_col_name

    def project(self, *col_names: str) -> None:
        self.drop(*(set(self._keys) - set(col_names)))
        self._keys = list(col_names)

    def is_empty(self, col_name: str) -> bool:
        col = self.column(col_name)