If you're interested in what it would take to put relational databases back on the rigorous footing of relational algebras, the Third Manifesto is a good place

If you're interested in what it would take to put relational databases back on the rigorous footing of relational algebras, the Third Manifesto is a good place to start. https://www.dcs.warwick.ac.uk/~hugh/TTM/DTATRM.pdf https://www.dcs.warwick.ac.uk/~hugh/TTM/DTATRM.pdf I find it somewhat sad that an implementation of a database with a proper D language hasn't broken out and become a ubiquitous tool for the profession. There were some proprietary versions shortly after the manifesto's publication, but it never caught on.