Method get_reverse_expr

datafusion/physical-expr/src/window/aggregate.rs:184–213

(&self)

    }

    fn get_reverse_expr(&self) -> Option<Arc<dyn WindowExpr>> {
        self.aggregate.reverse_expr().map(|reverse_expr| {
            let reverse_window_frame = self.window_frame.reverse();
            if reverse_window_frame.is_ever_expanding() {
                Arc::new(PlainAggregateWindowExpr::new(
                    Arc::new(reverse_expr),
                    &self.partition_by.clone(),
                    &self
                        .order_by
                        .iter()
                        .map(|e| e.reverse())
                        .collect::<Vec<_>>(),
                    Arc::new(self.window_frame.reverse()),
                    self.filter.clone(),
                )) as _
            } else {
                Arc::new(SlidingAggregateWindowExpr::new(
                    Arc::new(reverse_expr),
                    &self.partition_by.clone(),
                    &self
                        .order_by
                        .iter()
                        .map(|e| e.reverse())
                        .collect::<Vec<_>>(),
                    Arc::new(self.window_frame.reverse()),
                    self.filter.clone(),
                )) as _
            }
        })
    }

    fn uses_bounded_memory(&self) -> bool {
        !self.window_frame.end_bound.is_unbounded()