pathwaycom/pathway · error · ValueError

If max_difference is a Duration, the values of a column must

Error message

If max_difference is a Duration, the values of a column must either have a type of DateTimeUtc, DateTimeNaive or Duration. However, the column '{column}' has type '{column_type.typehint}'

What it means

Error "If max_difference is a Duration, the values of a column must either have a type of DateTimeUtc, DateTimeNaive or Duration. However, the column '{column}' has type '{column_type.typehint}'" thrown in pathwaycom/pathway.

Source

Thrown at python/pathway/io/_synchronization.py:327

def _check_column_type(column, max_difference):
    column_type = column._column.dtype
    if column_type not in _SUPPORTED_COLUMN_DTYPES:
        raise ValueError(
            f"Fields of type {column_type.typehint} are not supported in connector groups"
        )
    if isinstance(max_difference, int) and column_type != dtype.INT:
        raise ValueError(
            "If max_difference is an integer value, the values of a column must have a type of "
            f"int. However, the column '{column}' has type '{column_type.typehint}'"
        )
    if isinstance(max_difference, datetime.timedelta) and column_type not in (
        dtype.DATE_TIME_NAIVE,
        dtype.DATE_TIME_UTC,
        dtype.DURATION,
    ):
        raise ValueError(
            "If max_difference is a Duration, the values of a column must either have a type of "
            f"DateTimeUtc, DateTimeNaive or Duration. However, the column '{column}' "
            f"has type '{column_type.typehint}'"
        )

View on GitHub (pinned to fa2f74a464)

Solutions

1. When max_difference is a Duration, use a column of type DateTimeUtc, DateTimeNaive or Duration; cast or convert the column to one of these types first.

Example fix

t = t.select(ts=t.ts.strptime(fmt='%Y-%m-%d %H:%M:%S', contains_timezone=False))

When it happens

Trigger: Thrown at python/pathway/io/_synchronization.py:327 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/f2731e963994e067. Report an issue: GitHub.