Class JoinResult

python/pathway/internals/joins.py:553–1121

Result of a join between tables. 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(''' ...

class JoinResult(Joinable, OperatorInput):
    """Result of a join between tables.

    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 size
    ... 11   10  Alice    3    M
    ... 12    9    Bob    1    L
    ... 13    8    Tom    1   XL
    ... ''')
    >>> joinresult= t1.join(t2, t1.pet == t2.pet, t1.owner == t2.owner)   # noqa: E501
    >>> isinstance(joinresult, pw.JoinResult)
    True
    >>> pw.debug.compute_and_print(joinresult.select(t1.age, t2.size), include_id=False)
    age | size
    9   | L
    """

    _inner_table: Table
    _columns_mapping: dict[expr.InternalColRef, expr.ColumnReference]
    _left_table: Table
    _right_table: Table
    _original_left: Joinable
    _original_right: Joinable
    _substitution: dict[thisclass.ThisMetaclass, Joinable]
    _chained_join_desugaring: SubstitutionDesugaring
    _joined_on_names: StableSet[str]
    _all_colnames: StableSet[str]
    _join_mode: JoinMode

    def __init__(
        self,
        _context: clmn.Context,
        _inner_table: Table,
        _columns_mapping: dict[expr.InternalColRef, expr.ColumnReference],
        _left_table: Table,
        _right_table: Table,
        _original_left: Joinable,
        _original_right: Joinable,
        _substitution: dict[thisclass.ThisMetaclass, Joinable],
        _joined_on_names: StableSet[str],
        _join_mode: JoinMode,
    ):
        super().__init__(_context)
        self._inner_table = _inner_table
        self._columns_mapping = _columns_mapping
        self._left_table = _left_table
        self._right_table = _right_table
        self._substitution = {**_substitution, thisclass.this: self}
        self._joined_on_names = _joined_on_names