If I misunderstood the principles you refer to I apologize. Codd's relational rules and designs for relational databases developed from relational algebra theor

If I misunderstood the principles you refer to I apologize. Codd's relational rules and designs for relational databases developed from relational algebra theory, which was introduced by... Edgar F. Codd. https://en.m.wikipedia.org/wiki/Relational_algebra https://en.m.wikipedia.org/wiki/Relational_algebra If you meant to refer to some other principles can you name them or give a link or something?