Struct GraphCatalog 

pub struct GraphCatalog {
    pub label_counts: HashMap<Label, usize>,
    pub generation: u64,
    /* private fields */
}

Incrementally maintained graph catalog for cost-based optimization.

Extends (does not replace) the existing GraphStatistics. New planner uses GraphCatalog; old planner path keeps working.

Fields

label_counts: HashMap<Label, usize>

Node count per label

generation: u64

Monotonically increasing version for cache invalidation

Implementations

impl GraphCatalog

pub fn new() -> Self

Create a new empty catalog

pub fn on_label_added(&mut self, label: &Label)

Notify the catalog that a label was added to a node

pub fn on_label_removed(&mut self, label: &Label)

Notify the catalog that a label was removed from a node (e.g., node deleted)

pub fn on_edge_created( &mut self, source_id: NodeId, src_labels: &[Label], edge_type: &EdgeType, target_id: NodeId, tgt_labels: &[Label], )

Notify the catalog that an edge was created

For a multi-label source and multi-label target, this generates one triple entry per (src_label, edge_type, tgt_label) combination.

pub fn on_edge_deleted( &mut self, source_id: NodeId, src_labels: &[Label], edge_type: &EdgeType, target_id: NodeId, tgt_labels: &[Label], )

Notify the catalog that an edge was deleted

pub fn get_triple_stats(&self, pattern: &TriplePattern) -> Option<&TripleStats>

Get triple stats for a specific pattern

pub fn all_triple_stats(&self) -> &HashMap<TriplePattern, TripleStats>

Get all triple stats

pub fn estimate_label_scan(&self, label: &Label) -> f64

Estimate the number of rows from a label scan

pub fn estimate_expand_out( &self, source_label: &Label, edge_type: &EdgeType, ) -> f64

Estimate cardinality after an outgoing expand from source_label via edge_type

pub fn estimate_expand_in( &self, target_label: &Label, edge_type: &EdgeType, ) -> f64

Estimate cardinality after an incoming expand to target_label via edge_type

pub fn estimate_edge_existence( &self, source_label: &Label, edge_type: &EdgeType, target_label: &Label, ) -> f64

Estimate the probability that an edge exists between a specific source and target

pub fn recompute_full(store: &GraphStore) -> Self

Recompute all catalog statistics from scratch using the graph store. Used for consistency checks — result should match incrementally maintained stats.

pub fn format(&self) -> String

Format catalog as human-readable text for EXPLAIN output

pub fn clear(&mut self)

Reset catalog to empty state

Trait Implementations

impl Clone for GraphCatalog

fn clone(&self) -> GraphCatalog

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for GraphCatalog

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

Formats the value using the given formatter.