Hey Gavin, I had never heard of SPARQL, it appears to be an RDF/triplestore language. > This is really great -- it means that you can now execute graph-based > queries against Calcite's adapters! >
You're right, my bad for not having introduced SPARQL. It is indeed a query language for triplestores/quadstores, so I think what I've done with the adapter is kind of the contrary of what you mentioned here: it can be used to run SQL queries on triplestores that only support SPARQL for querying, actually exposing a sort of table view of the underlying graph. > From brief googling, it seems there are implementations of SPARQL that run > on top of major DB's like Postgres/MySQL. > So this could be used with the JDBC adapter then I assume? > If you mean to use SPARQL a bit like you've done with GraphQL (in the "other direction", i.e. in place of SQL to query non-graph DBs) then I think yes. > > "I have also planned to share some notes on the process of creating an > adapter from scratch, since there are > many moving parts (and I may have missed or misunderstood several)." > > This would be great, you appear to have a better understanding of the > pieces of Calcite and have implemented a lot more custom behavior. > Would love to read a walkthrough/explainer or guide and it would likely be > invaluable to others. > Absolutely. It took some effort to put all the pieces in place, and I'd be glad to share my experience with that. Nicola
