Struct PercentileDiscAccumulator 

pub struct PercentileDiscAccumulator { /* private fields */ }

Accumulator for the ordered-set aggregate PERCENTILE_DISC (issue #148).

Buffers (sort_keys, value) pairs, sorts them at finalize, and returns the first value whose cumulative distribution reaches the fraction: index = max(ceil(fraction * n) - 1, 0) — PostgreSQL 16 semantics (D5). NULL sort values are excluded; an empty group yields NULL. Partial state is rejected: ordered-set aggregation always runs in Single mode (D11).

Implementations

impl PercentileDiscAccumulator

pub fn new(fraction: f64, sort_specs: Vec<(bool, bool)>) -> Self

Trait Implementations

impl Accumulator for PercentileDiscAccumulator

fn update(&mut self, value: Option<SqlValue>) -> Result<()>

Update the accumulator with a new value (None for COUNT(*) rows).

fn update_ordered( &mut self, value: Option<SqlValue>, sort_keys: &[SqlValue], ) -> Result<()>

Update with the row’s aggregate-local sort key values (issue #148).

fn finalize(&self) -> Result<SqlValue>

Finalize the accumulator and return the resulting SqlValue.

fn state(&self) -> Result<Vec<SqlValue>>

Return the serializable partial aggregate state.

fn merge(&mut self, _state: &[SqlValue]) -> Result<()>

Merge a partial state produced by an accumulator of the same function.

fn clone_box(&self) -> Box<dyn Accumulator>

Clone the accumulator as a trait object.

fn retained_bytes(&self) -> u64

Estimated bytes retained by dynamically allocated accumulator state.

impl Clone for PercentileDiscAccumulator

fn clone(&self) -> PercentileDiscAccumulator

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PercentileDiscAccumulator

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

Formats the value using the given formatter.