Struct GraphStatistics 

pub struct GraphStatistics { /* private fields */ }

Graph statistics for query optimization

Collects and maintains statistical information about the RDF graph for use in cost-based query optimization.

Implementations

impl GraphStatistics

pub fn new() -> Self

Create a new graph statistics collector

pub fn record_insert(&self, triple: &Triple) -> Result<(), OxirsError>

Update statistics after inserting a triple

pub fn record_remove(&self, triple: &Triple) -> Result<(), OxirsError>

Update statistics after removing a triple

pub fn total_triples(&self) -> u64

Get total number of triples

pub fn get_predicate_stats( &self, predicate: &str, ) -> Option<PredicateStatistics>

Get statistics for a specific predicate

pub fn estimate_pattern_cardinality(&self, pattern: &TriplePattern) -> u64

Estimate cardinality for a triple pattern

pub fn estimate_algebra_pattern_cardinality( &self, pattern: &AlgebraTriplePattern, ) -> u64

Estimate cardinality for algebra triple pattern

pub fn record_query_execution( &self, stats: QueryExecutionStats, ) -> Result<(), OxirsError>

Record actual query execution for adaptive learning

pub fn get_learned_selectivity(&self, pattern_signature: &str) -> Option<f64>

Get learned selectivity for a pattern

pub fn export_to_json(&self) -> Result<String, OxirsError>

Export statistics to JSON for persistence

pub fn import_from_json(&self, json: &str) -> Result<(), OxirsError>

Import statistics from JSON

pub fn recompute_from_triples( &self, triples: &[Triple], ) -> Result<(), OxirsError>

Full statistics recomputation (expensive operation)

pub fn summary(&self) -> StatisticsSummary

Get all statistics as a summary

Trait Implementations

impl Clone for GraphStatistics

fn clone(&self) -> GraphStatistics

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for GraphStatistics

fn default() -> Self

Returns the “default value” for a type.