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This pdf document is a lecture slide from a Turkish university.
Here the lecturer introduced a technique to normalize database data that seems to involve pen and paper (Page-3).
What does he mean by R1, R2, R3, etc… and FD1, FD2, FD3, etc…
Can anyone provide me with any reference supporting this technique?
R means “Relation” (think table schema) and FD means “Functional Dependency”.
A Functional Dependency describe what attributes “determine” other values within a Relation. By fully reducing the FDs the Candidate Keys are left (and new Relations may be exposed). One of these Candidate Keys will be the Primary Key. (Of course, it is common these days to just have a Surrogate Primary Key — which is sometimes a subject of controversy — and thus the Candidate Keys all become Secondary Keys).
Just from Wikipedia (which is a fairly good place to start), see Relational Model, Database Normalization and Boyce-Codd normal form. (Note that BCNF is not always possible depending upon the FDs.)
Happy coding.
It’s been forever and I can’t find my old textbook, but Fundamentals of Database Systems: Functional Dependencies and Normalization for Relational Databases seems more like a gentle primer — it lacks on showing the application of the Armstrong’s Rules though, from what an I can tell.