Struct SqliteGraphBackend 

pub struct SqliteGraphBackend {
    conn: Mutex<Connection>,
    db_path: Option<PathBuf>,
}

SQLite-based graph backend.

Concurrency Model

Uses a Mutex<Connection> for thread-safe access. WAL mode and busy_timeout handle concurrent access gracefully.

Schema

Three tables store the knowledge graph:

• graph_entities: Entity nodes with temporal metadata
• graph_relationships: Directed edges between entities
• graph_entity_mentions: Links between entities and memories

Fields

conn: Mutex<Connection>

Connection to the SQLite database.

db_path: Option<PathBuf>

Path to the database (None for in-memory).

Implementations

impl SqliteGraphBackend

pub fn new(db_path: impl Into<PathBuf>) -> Result<Self>

Creates a new SQLite graph backend.

Errors

Returns an error if the database cannot be opened or initialized.

pub fn in_memory() -> Result<Self>

Creates an in-memory SQLite graph backend (useful for testing).

Errors

Returns an error if the database cannot be initialized.

pub fn db_path(&self) -> Option<&Path>

Returns the database path.

fn initialize(&self) -> Result<()>

Initializes the database schema.

fn create_indexes(conn: &Connection)

Creates indexes for optimized queries.

fn parse_entity_row(row: &Row<'_>) -> Result<Entity>

Parses an entity from a database row.

fn parse_relationship_row(row: &Row<'_>) -> Result<Relationship>

Parses a relationship from a database row.

fn build_entity_where_clause( query: &EntityQuery, ) -> (String, Vec<Box<dyn ToSql>>)

Builds WHERE clause conditions for entity queries.

Trait Implementations

impl GraphBackend for SqliteGraphBackend

fn store_entity(&self, entity: &Entity) -> Result<()>

Stores an entity in the graph.

fn get_entity(&self, id: &EntityId) -> Result<Option<Entity>>

Retrieves an entity by ID.

fn query_entities(&self, query: &EntityQuery) -> Result<Vec<Entity>>

Queries entities with optional filters.

fn delete_entity(&self, id: &EntityId) -> Result<bool>

Deletes an entity by ID.

fn merge_entities( &self, entity_ids: &[EntityId], canonical_name: &str, ) -> Result<Entity>

Merges multiple entities into a canonical entity.

fn find_entities_by_name( &self, name: &str, entity_type: Option<EntityType>, domain: Option<&Domain>, limit: usize, ) -> Result<Vec<Entity>>

Finds entities by name using fuzzy matching.

fn store_relationship(&self, relationship: &Relationship) -> Result<()>

Stores a relationship in the graph.

fn query_relationships( &self, query: &RelationshipQuery, ) -> Result<Vec<Relationship>>

Queries relationships with optional filters.

fn delete_relationships(&self, query: &RelationshipQuery) -> Result<usize>

Deletes relationships matching the query.

fn get_relationship_types( &self, from_entity: &EntityId, to_entity: &EntityId, ) -> Result<Vec<RelationshipType>>

Gets all relationship types between two entities.

fn store_mention(&self, mention: &EntityMention) -> Result<()>

Stores an entity mention (link between entity and memory).

fn get_mentions_for_entity( &self, entity_id: &EntityId, ) -> Result<Vec<EntityMention>>

Gets all mentions of an entity.

fn get_entities_in_memory(&self, memory_id: &MemoryId) -> Result<Vec<Entity>>

Gets all entities mentioned in a memory.

fn delete_mentions_for_entity(&self, entity_id: &EntityId) -> Result<usize>

Deletes all mentions of an entity.

fn delete_mentions_for_memory(&self, memory_id: &MemoryId) -> Result<usize>

Deletes all entity mentions for a memory.

fn traverse( &self, start: &EntityId, max_depth: u32, relationship_types: Option<&[RelationshipType]>, min_confidence: Option<f32>, ) -> Result<TraversalResult>

Traverses the graph from a starting entity.

fn find_path( &self, from: &EntityId, to: &EntityId, max_depth: u32, ) -> Result<Option<TraversalResult>>

Finds the shortest path between two entities.

fn query_entities_at( &self, query: &EntityQuery, point: &BitemporalPoint, ) -> Result<Vec<Entity>>

Queries entities at a specific point in bitemporal space.

fn query_relationships_at( &self, query: &RelationshipQuery, point: &BitemporalPoint, ) -> Result<Vec<Relationship>>

Queries relationships at a specific point in bitemporal space.

fn close_entity_valid_time(&self, id: &EntityId, end_time: i64) -> Result<()>

Closes (ends) an entity’s valid time at the given timestamp.

fn close_relationship_valid_time( &self, from_entity: &EntityId, to_entity: &EntityId, relationship_type: RelationshipType, end_time: i64, ) -> Result<()>

Closes (ends) a relationship’s valid time at the given timestamp.

fn get_stats(&self) -> Result<GraphStats>

Returns statistics about the graph.

fn clear(&self) -> Result<()>

Clears all graph data.

fn get_related_entities( &self, entity_id: &EntityId, max_depth: u32, limit: usize, ) -> Result<Vec<Entity>>

Gets entities related to a given entity within N hops.