In computer science, domain relational calculus (DRC) is a calculus that was introduced by Michel Lacroix and Alain Pirotte as a declarative database query language for the relational data model.
In DRC, queries have the form:
where each Xi is either a domain variable or constant, and denotes a DRC formula. The result of the query is the set of tuples Xi to Xn which makes the DRC formula true.
This language uses the same operators as tuple calculus, the logical connectives ∧ (and), ∨ (or) and ¬ (not). The existential quantifier (∃) and the universal quantifier (∀) can be used to bind the variables.
Its computational expressiveness is equivalent to that of Relational algebra.
Read more about Domain Relational Calculus: Examples
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