Method ignore_late

python/pathway/internals/table.py:852–895

Filter out entries that satisfy ``time_column <= max(time_column) - threshold``. In contrast to ``forget``, this operator doesn't store the entries. It just checks if the entries match the condition and, if they do, allows them to pass. The only value stored by this operator

(
        self, time_column: expr.ColumnExpression, threshold: IntervalType
    )

    @trace_user_frame
    @desugar
    def ignore_late(
        self, time_column: expr.ColumnExpression, threshold: IntervalType
    ) -> Table[TSchema]:
        """Filter out entries that satisfy ``time_column <= max(time_column) - threshold``.

        In contrast to ``forget``, this operator doesn&#x27;t store the entries. It just checks
        if the entries match the condition and, if they do, allows them to pass. The only
        value stored by this operator is the current time (defined as max over all
        ``time_column`` values so far).

        Please note that if the table is non-append-only and there&#x27;s a difference in
        processing time between an insertion and a deletion for some key, the insertion
        may pass through but the deletion may be filtered out. It&#x27;ll happen if the max
        value in ``time_column`` advanced between the insertion and deletion and the insertion
        didn&#x27;t satisfy the filtering-out criterion but the deletion did.

        Args:
            time_column: ``ColumnExpression`` that specifies the event time.
            threshold: value used to determine which entries should be filtered out.
                Should match the type of the ``time_column`` (``int -> int``,
                ``float -> float``, ``datetime -> timedelta``).

        Example:

        >>> import pathway as pw
        >>> t = pw.debug.table_from_markdown(
        ...     ''&#x27;
        ...     t | v | __time__
        ...     1 | 1 |     2
        ...     2 | 2 |     4
        ...     5 | 3 |     6
        ...     2 | 4 |     8
        ...     7 | 5 |    10
        ... ''&#x27;
        ... )
        >>> res = t.ignore_late(pw.this.t, 3)
        >>> pw.debug.compute_and_print_update_stream(res)
                    | t | v | __time__ | __diff__
        ^X1MXHYY... | 1 | 1 | 2        | 1
        ^YYY4HAB... | 2 | 2 | 4        | 1
        ^Z3QWT29... | 5 | 3 | 6        | 1
        ^3HN31E1... | 7 | 5 | 10       | 1
        """
        return self._freeze(time_column + threshold, time_column)

    @trace_user_frame
    @desugar