Struct GraphProjection 

pub struct GraphProjection { /* private fields */ }

A read-only, filtered view of a graph store.

Delegates all reads to the inner store, filtering results by the ProjectionSpec. Nodes without matching labels and edges without matching types are invisible.

Implementations

impl GraphProjection

pub fn new(inner: Arc<dyn GraphStoreSearch>, spec: ProjectionSpec) -> Self

Creates a new projection over the given store.

Trait Implementations

impl GraphStore for GraphProjection

fn get_edge_versioned( &self, id: EdgeId, epoch: EpochId, transaction_id: TransactionId, ) -> Option<Edge>

Returns a versioned edge if it passes projection filters.

Limitation: edge_matches checks endpoint visibility via get_node (current snapshot), not get_node_versioned, because GraphProjection does not store epoch/transaction context. This means endpoint filtering may reflect the current state rather than the requested version.

fn edge_type_versioned( &self, id: EdgeId, epoch: EpochId, transaction_id: TransactionId, ) -> Option<ArcStr>

Returns the type of a versioned edge if it passes projection filters.

Limitation: endpoint visibility is checked via get_node (current snapshot), not get_node_versioned. See get_edge_versioned for details.

fn get_node(&self, id: NodeId) -> Option<Node>

Returns a node by ID (latest visible version at current epoch).

fn get_edge(&self, id: EdgeId) -> Option<Edge>

Returns an edge by ID (latest visible version at current epoch).

fn get_node_versioned( &self, id: NodeId, epoch: EpochId, transaction_id: TransactionId, ) -> Option<Node>

Returns a node visible to a specific transaction.

fn get_node_at_epoch(&self, id: NodeId, epoch: EpochId) -> Option<Node>

Returns a node using pure epoch-based visibility (no transaction context).

fn get_edge_at_epoch(&self, id: EdgeId, epoch: EpochId) -> Option<Edge>

Returns an edge using pure epoch-based visibility (no transaction context).

fn get_node_property(&self, id: NodeId, key: &PropertyKey) -> Option<Value>

Gets a single property from a node without loading all properties.

fn get_edge_property(&self, id: EdgeId, key: &PropertyKey) -> Option<Value>

Gets a single property from an edge without loading all properties.

fn get_node_property_batch( &self, ids: &[NodeId], key: &PropertyKey, ) -> Vec<Option<Value>>

Gets a property for multiple nodes in a single batch operation.

fn get_nodes_properties_batch( &self, ids: &[NodeId], ) -> Vec<FxHashMap<PropertyKey, Value>>

Gets all properties for multiple nodes in a single batch operation.

fn get_nodes_properties_selective_batch( &self, ids: &[NodeId], keys: &[PropertyKey], ) -> Vec<FxHashMap<PropertyKey, Value>>

Gets selected properties for multiple nodes (projection pushdown).

fn get_edges_properties_selective_batch( &self, ids: &[EdgeId], keys: &[PropertyKey], ) -> Vec<FxHashMap<PropertyKey, Value>>

Gets selected properties for multiple edges (projection pushdown).

fn neighbors(&self, node: NodeId, direction: Direction) -> Vec<NodeId>

Returns neighbor node IDs in the specified direction.

fn edges_from( &self, node: NodeId, direction: Direction, ) -> Vec<(NodeId, EdgeId)>

Returns (target_node, edge_id) pairs for edges from a node.

fn out_degree(&self, node: NodeId) -> usize

Returns the out-degree of a node (number of outgoing edges).

fn in_degree(&self, node: NodeId) -> usize

Returns the in-degree of a node (number of incoming edges).

fn has_backward_adjacency(&self) -> bool

Whether backward adjacency is available for incoming edge queries.

fn node_ids(&self) -> Vec<NodeId>

Returns all non-deleted node IDs, sorted by ID.

fn all_node_ids(&self) -> Vec<NodeId>

Returns all node IDs including uncommitted/PENDING versions.

fn nodes_by_label(&self, label: &str) -> Vec<NodeId>

Returns node IDs with a specific label.

fn node_count(&self) -> usize

Returns the total number of non-deleted nodes.

fn edge_count(&self) -> usize

Returns the total number of non-deleted edges.

fn edge_type(&self, id: EdgeId) -> Option<ArcStr>

Returns the type string of an edge.

fn has_property_index(&self, property: &str) -> bool

Returns true if a property index exists for the given property.

fn find_nodes_by_property(&self, property: &str, value: &Value) -> Vec<NodeId>

Finds all nodes with a specific property value. Uses indexes when available.

fn find_nodes_by_properties(&self, conditions: &[(&str, Value)]) -> Vec<NodeId>

Finds nodes matching multiple property equality conditions.

fn find_nodes_in_range( &self, property: &str, min: Option<&Value>, max: Option<&Value>, min_inclusive: bool, max_inclusive: bool, ) -> Vec<NodeId>

Finds nodes whose property value falls within a range.

fn node_property_might_match( &self, property: &PropertyKey, op: CompareOp, value: &Value, ) -> bool

Returns true if a node property predicate might match any nodes. Uses zone maps for early filtering.

fn edge_property_might_match( &self, property: &PropertyKey, op: CompareOp, value: &Value, ) -> bool

Returns true if an edge property predicate might match any edges.

fn statistics(&self) -> Arc<Statistics>

Returns the current statistics snapshot (cheap Arc clone).

fn estimate_label_cardinality(&self, label: &str) -> f64

Estimates cardinality for a label scan.

fn estimate_avg_degree(&self, edge_type: &str, outgoing: bool) -> f64

Estimates average degree for an edge type.

fn current_epoch(&self) -> EpochId

Returns the current MVCC epoch.

fn all_labels(&self) -> Vec<String>

Returns all label names in the database.

fn all_edge_types(&self) -> Vec<String>

Returns all edge type names in the database.

fn all_property_keys(&self) -> Vec<String>

Returns all property key names used in the database.

fn is_node_visible_at_epoch(&self, id: NodeId, epoch: EpochId) -> bool

Checks if a node is visible at the given epoch without building the full Node.

fn is_node_visible_versioned( &self, id: NodeId, epoch: EpochId, transaction_id: TransactionId, ) -> bool

Checks if a node is visible to a specific transaction without building the full Node.

fn is_edge_visible_at_epoch(&self, id: EdgeId, epoch: EpochId) -> bool

Checks if an edge is visible at the given epoch without building the full Edge.

fn is_edge_visible_versioned( &self, id: EdgeId, epoch: EpochId, transaction_id: TransactionId, ) -> bool

Checks if an edge is visible to a specific transaction without building the full Edge.

fn filter_visible_node_ids(&self, ids: &[NodeId], epoch: EpochId) -> Vec<NodeId>

Filters node IDs to only those visible at the given epoch (batch).

fn filter_visible_node_ids_versioned( &self, ids: &[NodeId], epoch: EpochId, transaction_id: TransactionId, ) -> Vec<NodeId>

Filters node IDs to only those visible to a transaction (batch).

fn get_node_history(&self, _id: NodeId) -> Vec<(EpochId, Option<EpochId>, Node)>

Returns all versions of a node with their creation/deletion epochs, newest first.

fn get_edge_history(&self, _id: EdgeId) -> Vec<(EpochId, Option<EpochId>, Edge)>

Returns all versions of an edge with their creation/deletion epochs, newest first.

impl GraphStoreSearch for GraphProjection