Crate lance_graph 

Lance Graph Query Engine

This crate provides graph query capabilities for Lance datasets using Cypher syntax. It interprets Lance datasets as property graphs and translates Cypher queries into DataFusion SQL queries for execution.

Features

• Cypher query parsing and AST representation
• Graph pattern matching on columnar data
• Property graph interpretation of Lance datasets
• Translation to optimized SQL via DataFusion
• Support for nodes, relationships, and properties

Example

use lance_graph::{CypherQuery, GraphConfig, Result};

let config = GraphConfig::builder()
    .with_node_label("Person", "person_id")
    .with_relationship("KNOWS", "src_person_id", "dst_person_id")
    .build()?;

let query = CypherQuery::new("MATCH (p:Person) WHERE p.age > 30 RETURN p.name")?
    .with_config(config);

// Execute against a dataset (would need actual dataset integration)
// let results = query.execute(&dataset).await?;

Re-exports

pub use config::GraphConfig;

pub use config::NodeMapping;

pub use config::RelationshipMapping;

pub use error::GraphError;

pub use error::Result;

pub use query::CypherQuery;

pub use query::ExecutionStrategy;

Modules

ast

Abstract Syntax Tree for Cypher queries

config

Graph configuration for mapping Lance datasets to property graphs

datafusion_planner

DataFusion-based physical planner for graph queries

error

Error types for the Lance graph query engine

lance_native_planner

Lance Native physical planner (placeholder)

logical_plan

Logical planning for graph queries

parser

Cypher query parser

query

High-level Cypher query interface for Lance datasets

query_processor

Unified query processor implementing the full pipeline

semantic

Semantic analysis for graph queries

simple_executor

Simple single-table query executor with limited Cypher feature support

source_catalog

Context-free source catalog for DataFusion logical planning.

sql_converter

SQL converter for logical plans

Constants

MAX_VARIABLE_LENGTH_HOPS

Maximum allowed hops for variable-length relationship expansion (e.g., *1..N)