Relation Algebra ≠ Relational Algebra
11 hours ago
- Many people confuse relation algebra with relational algebra, a mix-up that even affected Wikipedia and some database experts.
- Relational algebra, introduced by Ted Codd in 1970, is the foundation for relational databases and is equivalent to domain independent relational calculus.
- Relation algebra, from logic and pure math, is an algebraic structure based on binary relations and is equivalent to first-order logic with at most three variables (FOL^3).
- Relation algebra has found applications in computer science, notably in the Alloy analyzer, which uses 'relational logic'.
- A dedicated group led by Dirk Van Gucht applies relation algebra to database theory, leading to the Prela query language, the first based on relation algebra since IUGQL.
- The author suggests renaming relation algebra to 'Tarski's Algebra of Relations' (TAR) to avoid future confusion.