Function mz_expr::relation::func::window_aggr

fn window_aggr<'a, I, A>(
    input_datums: I,
    callers_temp_storage: &'a RowArena,
    wrapped_aggregate: &AggregateFunc,
    order_by: &[ColumnOrder],
    window_frame: &WindowFrame,
) -> Datum<'a>
where
    I: IntoIterator<Item = Datum<'a>>,
    A: OneByOneAggr,

input_datums is an entire window partition. The expected input is in the format of [((OriginalRow, InputValue), OrderByExprs...)] See also in the comment in window_func_applied_to.

wrapped_aggregate: e.g., for sum(...) OVER (...), this is the sum(...).

Note that this order_by doesn’t have expressions, only ColumnOrders. For an explanation, see the comment on WindowExprType.