Enum Boundedness

pub enum Boundedness {
    Bounded,
    Unbounded {
        requires_infinite_memory: bool,
    },
}

Represents whether a stream of data generated by an operator is bounded (finite) or unbounded (infinite).

This is used to determine whether an execution plan will eventually complete processing all its data (bounded) or could potentially run forever (unbounded).

For unbounded streams, it also tracks whether the operator requires finite memory to process the stream or if memory usage could grow unbounded.

Boundedness of the output stream is based on the the boundedness of the input stream and the nature of the operator. For example, limit or topk with fetch operator can convert an unbounded stream to a bounded stream.

Variants

Bounded

The data stream is bounded (finite) and will eventually complete

Unbounded

The data stream is unbounded (infinite) and could run forever

Fields

requires_infinite_memory: bool

Whether this operator requires infinite memory to process the unbounded stream. If false, the operator can process an infinite stream with bounded memory. If true, memory usage may grow unbounded while processing the stream.

For example, Median requires infinite memory to compute the median of an unbounded stream. Min/Max requires infinite memory if the stream is unordered, but can be computed with bounded memory if the stream is ordered.

Implementations

impl Boundedness

pub fn is_unbounded(&self) -> bool

Trait Implementations

impl Clone for Boundedness

fn clone(&self) -> Boundedness

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Boundedness

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

Formats the value using the given formatter.

impl PartialEq for Boundedness

fn eq(&self, other: &Boundedness) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Boundedness

impl Eq for Boundedness

impl StructuralPartialEq for Boundedness