A DRC Query has the form:
where each Xi is either a domain variable or constant, and p(<X1, X2, .... , Xn>) denotes a DRC Formula. The result of the query is set of tuples Xi to Xn which makes the DRC formula true.
This language uses the same operators as tuple calculus; Logicial operators ∧ (and), ∨ (or) and ¬ (not), and we can use the existential quantifier (∃) and the universal quantifier (∀) to bind the variables.
Here are examples of DRC:
Let's take A,B1,C to mean Rank, Name, ID and D,E,F to mean Name, DeptName, ID
Find all Captains of the Enterprise:
Find Names of Enterprise crewmembers who are in Stellar Cartography:
=== Work In Progress ===, feel free to add.
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