aplbrain / grand-cypher

Implementation of the Cypher language for searching NetworkX graphs
Apache License 2.0
83 stars 8 forks source link
cypher grand graph graph-database neo4j networks networkx python

GrandCypher

GitHub Workflow Status (branch)
pip install grand-cypher
# Note: You will want a version of grandiso>=2.2.0 for best performance!
# pip install -U 'grandiso>=2.2.0'

GrandCypher is a partial (and growing!) implementation of the Cypher graph query language written in Python, for Python data structures.

You likely already know Cypher from the Neo4j Graph Database. Use it with your favorite graph libraries in Python!

Usage

Example Usage with NetworkX:

from grandcypher import GrandCypher
import networkx as nx

GrandCypher(nx.karate_club_graph()).run("""
MATCH (A)-[]->(B)
MATCH (B)-[]->(C)
WHERE A.club == "Mr. Hi"
RETURN A.club, B.club
""")

See examples.md for more!

Example Usage with SQL

Create your own "Sqlite for Neo4j"! This example uses grand-graph to run queries in SQL:

import grand
from grandcypher import GrandCypher

G = grand.Graph(
    backend=grand.backends.SQLBackend(
        db_url="my_persisted_graph.db",
        directed=True
    )
)

# use the networkx-style API for the Grand library:
G.nx.add_node("A", foo="bar")
G.nx.add_edge("A", "B")
G.nx.add_edge("B", "C")
G.nx.add_edge("C", "A")

GrandCypher(G.nx).run("""
MATCH (A)-[]->(B)-[]->(C)
MATCH (C)-[]->(A)
WHERE
    A.foo == "bar"
RETURN
    A, B, C
""")

Feature Parity

Feature Support
Multiple MATCH clauses
WHERE-clause filtering on nodes
Anonymous -[]- edges
LIMIT
SKIP
Node/edge attributes with {} syntax
WHERE-clause filtering on edges
Named -[]- edges
Chained ()-[]->()-[]->() edges ✅ Thanks @khoale88!
Backwards ()<-[]-() edges ✅ Thanks @khoale88!
Anonymous () nodes ✅ Thanks @khoale88!
Undirected ()-[]-() edges ✅ Thanks @khoale88!
Boolean Arithmetic (AND/OR) ✅ Thanks @khoale88!
(:Type) node-labels ✅ Thanks @khoale88!
[:Type] edge-labels ✅ Thanks @khoale88!
DISTINCT ✅ Thanks @jackboyla!
ORDER BY ✅ Thanks @jackboyla!
Aggregation functions (COUNT, SUM, MIN, MAX, AVG) ✅ Thanks @jackboyla!
Aliasing of returned entities (return X as Y) ✅ Thanks @jackboyla!
Negated edges (where not (a)-->(b)) 🥺
OPTIONAL MATCH 🥺
Graph mutations (e.g. DELETE, SET,...) 🥺
✅ = Supported 🛣 = On Roadmap 🥺 = Help Welcome 🔴 = Not Planned

Citing

If this tool is helpful to your research, please consider citing it with:

# https://doi.org/10.1038/s41598-021-91025-5
@article{Matelsky_Motifs_2021,
    title={{DotMotif: an open-source tool for connectome subgraph isomorphism search and graph queries}},
    volume={11},
    ISSN={2045-2322},
    url={http://dx.doi.org/10.1038/s41598-021-91025-5},
    DOI={10.1038/s41598-021-91025-5},
    number={1},
    journal={Scientific Reports},
    publisher={Springer Science and Business Media LLC},
    author={Matelsky, Jordan K. and Reilly, Elizabeth P. and Johnson, Erik C. and Stiso, Jennifer and Bassett, Danielle S. and Wester, Brock A. and Gray-Roncal, William},
    year={2021},
    month={Jun}
}