Struct PropertyStatistics 

pub struct PropertyStatistics {
    pub property_name: String,
    pub tag_name: Option<String>,
    pub distinct_values: u64,
    pub min_value: Option<Value>,
    pub max_value: Option<Value>,
    pub histogram: Option<ValueHistogram>,
    pub use_histogram: bool,
    pub null_count: Option<u64>,
    pub total_rows: Option<u64>,
}

Attribute statistics information

Fields

property_name: String

Attribute name

tag_name: Option<String>

Associated Tags (optional)

distinct_values: u64

Number of different values

min_value: Option<Value>

Observed minimum value in the sampled window (orderable types only).

max_value: Option<Value>

Observed maximum value in the sampled window (orderable types only).

histogram: Option<ValueHistogram>

Optional histograms (enabled for attributes with a high cardinality)

use_histogram: bool

Is it appropriate to use a histogram? (Histograms are not necessary for attributes with a low cardinality.)

null_count: Option<u64>

Null count from the storage snapshot, when tracked.

total_rows: Option<u64>

Owning relation row count from the storage snapshot, when known.

Implementations

impl PropertyStatistics

pub fn new(property_name: String, tag_name: Option<String>) -> Self

Create new attribute statistics information.

pub fn with_histogram(self, histogram: ValueHistogram) -> Self

Setting up a histogram

pub fn should_use_histogram(&self) -> bool

Determine whether to use a histogram.

pub fn null_fraction(&self) -> Option<f64>

Null fraction nulls / rows when both sides are tracked.

pub fn observe_value(&mut self, value: &Value)

Record one observed value into the min/max envelope.

Numeric values compare across int and float kinds with the same numeric-aware rule as snapshot merging; string values compare lexicographically. Mixed numeric versus string columns keep the first-seen family. Numeric strings stay lexicographic.

Trait Implementations

impl Clone for PropertyStatistics

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 PropertyStatistics

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

Formats the value using the given formatter.

impl Default for PropertyStatistics

fn default() -> Self

Returns the “default value” for a type.