On: Show HN: Simple-graph – a graph database in SQLite

[lolive]

I wonder if there are ways, in SQLite, to build indices for s,p,o/s,p/p,o/ and maybe more subtle ones... That would be uber nice, given the fact that most graph databases have their own indexing strategies, and you cannot craft your own.

[JimmyRuska → lolive]

I saw this lecture some time back on the topic of implementation and tradeoffs https://www.youtube.com/watch?v=Dxwo9DYWV_c

[westurner → lolive]

rdflib-sqlalchemy is a SQLAlchemy rdflib graph store backend: https://github.com/RDFLib/rdflib-sqlalchemy

It also persists namespace mappings so that e.g. schema:Thing expands to http://schema.org/Thing

The table schema and indices are defined in rdflib_sqlalchemy/tables.py: https://github.com/RDFLib/rdflib-sqlalchemy/blob/develop/rdf...

You can execute SPARQL queries against SQL, but most native triplestores will have a better query plan and/or better performance.

Apache Rya, for example:

> indexes SPO, POS, and OSP.

[mark_l_watson → westurner]

Thanks for your comment. I use rdflib frequently but have never tried the SQLAlchemy back end. Now I will. That said, Jena or Fuseki, or the commercial RDF stores like GraphDB, Stardog, and Allegrograph are so much more efficient.