Struct Histogram 

pub struct Histogram {
    pub min: Vec<u8>,
    pub max: Vec<u8>,
    pub distinct: u64,
    pub buckets: [u32; 64],
    pub partial: bool,
}

Value-domain shape of one (kind, pid) for planner estimates: exact extrema and distinct count, plus an equi-width histogram over the order-preserving payload space. Computed on demand from the value dictionary; never a query result.

Fields

min: Vec<u8>

Smallest payload.

max: Vec<u8>

Largest payload.

distinct: u64

Distinct payloads.

buckets: [u32; 64]

Owner-occurrence counts per fixed bucket.

partial: bool

The walk that built this stopped at its budget: buckets, distinct and max cover only the walked (smallest) prefix of the value domain.

Implementations

impl Histogram

pub fn add(&mut self, payload: &[u8], count: u64)

Fold one distinct payload held by count owner-occurrences.

pub fn resident_bytes(&self) -> usize

Resident bytes, for cache accounting.

pub fn total(&self) -> u64

Total owner-occurrences across all buckets.

pub fn estimate(&self, bound: &[u8], above: bool) -> u64

Estimated owners satisfying a range bound (above = Gt/Gte), interpolating uniformly within the bound’s fixed bucket.

Trait Implementations

impl Clone for Histogram

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Histogram

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

Formats the value using the given formatter.

impl Default for Histogram

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Histogram

impl PartialEq for Histogram

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Histogram