Foundations of Databases (1995)
Chapter 3, 'The Structure of the Relational Model', has a helpful background on the origins of <i>table-oriented</i> relational algebra.  Unfortunately, it misses the importance of graphs, which afaict, transcend the dependence on tables' bias for normalized topologies of pathologically regular 2D metric spaces, and it even reinforces their relevance by saying, "Intuitively, the data is represented in tables...".  Whereas,<p>> Graphs allow us to build complex, intuitive relationships between data points. Unlike many traditional methods of structuring data, which focus on the <i>format</i> of relationships, graphs focus on the <i>topology</i> of relationships in the dataset.<p><a href="https://blog.usejournal.com/data-modelling-with-graph-theory-part-1-introduction-f52aaf11f974" rel="nofollow">https://blog.usejournal.com/data-modelling-with-graph-theory...</a><p>When it comes to making database concepts more intuitive, I find visually rich representations very helpful, for example using geometric space-encoded logical relationships to aid diagrammatic reasoning.<p>It goes along well with many other people's efforts to improve mathematical represenations and interfaces through intuitive visualizations, ie:<p><a href="https://intuitive-math.club/" rel="nofollow">https://intuitive-math.club/</a><p><a href="http://acko.net/" rel="nofollow">http://acko.net/</a><p><a href="https://www.reddit.com/r/mathgifs/" rel="nofollow">https://www.reddit.com/r/mathgifs/</a><p><a href="https://www.reddit.com/r/visualizedmath/" rel="nofollow">https://www.reddit.com/r/visualizedmath/</a><p>...