Method update_rows

python/pathway/internals/table.py:1776–1850

Updates rows of `self`, breaking ties in favor for the rows in `other`. Semantics: - result.columns == self.columns == other.columns - result.id == self.id ∪ other.id Requires: - other.columns == self.columns Args: other: the other tabl

(self, other: Table[TSchema])

    @trace_user_frame
    @check_arg_types
    def update_rows(self, other: Table[TSchema]) -> Table[TSchema]:
        """Updates rows of `self`, breaking ties in favor for the rows in `other`.

        Semantics:
        - result.columns == self.columns == other.columns
        - result.id == self.id ∪ other.id

        Requires:
        - other.columns == self.columns

        Args:
            other:  the other table.

        Returns:
            Table: `self` updated with rows form `other`.

        Example:

        >>> import pathway as pw
        >>> t1 = pw.debug.table_from_markdown('''
        ...   | age | owner | pet
        ... 1 | 10  | Alice | 1
        ... 2 | 9   | Bob   | 1
        ... 3 | 8   | Alice | 2
        ... ''')
        >>> t2 = pw.debug.table_from_markdown('''
        ...    | age | owner | pet
        ... 1  | 10  | Alice | 30
        ... 12 | 12  | Tom   | 40
        ... ''')
        >>> t3 = t1.update_rows(t2)
        >>> pw.debug.compute_and_print(t3, include_id=False)
        age | owner | pet
        8   | Alice | 2
        9   | Bob   | 1
        10  | Alice | 30
        12  | Tom   | 40
        """
        if other.keys() != self.keys():
            raise ValueError(
                "Columns do not match between argument of Table.update_rows() and the updated table."
            )
        if self._universe.is_subset_of(other._universe):
            warnings.warn(
                "Universe of self is a subset of universe of other in update_rows. Returning other.",
                stacklevel=5,
            )
            return other

        schema = {}

        for key in self.keys():
            schema[key] = _types_lca_with_error(
                self.schema._dtypes()[key],
                other.schema._dtypes()[key],
                function_name="an update_rows",
                pointers=False,
            )