So I see there's a new version of Stardog out, 7.0.2. Just a little minor bump. Maybe some bug fixes and then this little nugget "SQL query support for BI/viz tools (#7886)" Boom!
You might want to be all modest and nonchalant about it but I'm going to jump up and down about it like it's my birthday. This is awesome. I see you mention Tableau but I'm going to give Apache Superset a try with this. https://superset.incubator.apache.org/
Beyond just business reporting tools this opens up the field to a ton of tools and apps that are built for SQL. I love SPARQL but sometimes I either don't need the flexibility or I don't have the time to rewrite the world so that I can do some prototyping. Maybe hook this up to geoserver to serve some mapping data. This is going to be fun.
We are very excited about this new feature too and it is good to see others share the same enthusiasm. We have a blog post coming out about this new feature very soon and we will be talking about it more going forward.
This feature is in beta state right now so some bumps along the way are possible. As you mentioned we tested several BI tools and some other SQL systems but there are many others we have not tested yet. We would love to hear your experience with Apache Superset and any feedback you might have about this feature.
We looked into Apache Superset and discovered some minor compatibility issues mostly due to the underlying SQLAlchemy python library that is being used. So this is not going to work out-of-the-box with Stardog 7.0.2 but we are looking into these issues and hopefully we will fix them for the next release.