pathwaycom/pathway · error · NotImplementedError

window_join doesn't support windows of type intervals_over

Error message

window_join doesn't support windows of type intervals_over

What it means

Error "window_join doesn't support windows of type intervals_over" thrown in pathwaycom/pathway.

Source

Thrown at python/pathway/stdlib/temporal/_window.py:494

                instance=pw.this._pw_instance if instance is not None else None,
                sort_by=pw.this._pw_key,
                _is_window=True,
            )
        )

    @check_arg_types
    def _join(
        self,
        left: pw.Table,
        right: pw.Table,
        left_time_expression: pw.ColumnExpression,
        right_time_expression: pw.ColumnExpression,
        *on: pw.ColumnExpression,
        mode: pw.JoinMode,
        left_instance: pw.ColumnReference | None = None,
        right_instance: pw.ColumnReference | None = None,
    ) -> WindowJoinResult:
        raise NotImplementedError(
            "window_join doesn't support windows of type intervals_over"
        )


@check_arg_types
@trace_user_frame
def session(
    *,
    predicate: _SessionPredicateType | None = None,
    max_gap: int | float | datetime.timedelta | None = None,
) -> Window:
    """Allows grouping together elements within a window across ordered time-like
    data column by locally grouping adjacent elements either based on a maximum time
    difference or using a custom predicate.

    Note:
        Usually used as an argument of `.windowby()`.
        Exactly one of the arguments `predicate` or `max_gap` should be provided.

View on GitHub (pinned to fa2f74a464)

Solutions

1. Use sliding, tumbling, or session windows with window_join; intervals_over windows are not supported there.

Example fix

t1.window_join(t2, pw.temporal.sliding(duration=timedelta(hours=1)), ...)

When it happens

Trigger: Thrown at python/pathway/stdlib/temporal/_window.py:494 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of pathwaycom/pathway@fa2f74a464 (2026-08-15). Data as JSON: /api/errors/ce529c5da544b137. Report an issue: GitHub.