Struct WindowEvalContext 

#[non_exhaustive]
pub struct WindowEvalContext<'a> {
    pub most_recent_row: Option<&'a RecordBatch>,
}

Stream-level context passed to WindowExpr::evaluate_stateful.

This carries information that spans all partitions of the input, as opposed to the per-partition state in PartitionBatches and PartitionWindowAggStates. It is non_exhaustive so that fields can be added without breaking implementors; construct it with Default::default and the with_* builder methods.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

most_recent_row: Option<&'a RecordBatch>

A single-row batch containing the most recent input row, whichever partition that row belongs to. It is Some only when the input is ordered by the first ORDER BY column across partitions (Linear mode), in which case no future input row – in any partition – can precede it in that column; implementations can use this bound to decide whether pending window frames can be finalized before their partition receives more data.

Implementations

impl<'a> WindowEvalContext<'a>

pub fn with_most_recent_row(self, batch: Option<&'a RecordBatch>) -> Self

Sets the most recent input row (see Self::most_recent_row).

Trait Implementations

impl<'a> Clone for WindowEvalContext<'a>

fn clone(&self) -> WindowEvalContext<'a>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Copy for WindowEvalContext<'a>

impl<'a> Debug for WindowEvalContext<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a> Default for WindowEvalContext<'a>

fn default() -> WindowEvalContext<'a>

Returns the “default value” for a type.