In computer science,

**domain relational calculus**is a calculus that was introduced by Edgar F. Codd as part of the relational model in order to give a declarative database query language for this data model.

A DRC Query has the form:

_{i}is either a domain variable or constant, and p(

_{i}to X

_{n}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:

In this example, A,B1,C is the result set and a set in the table Enterprise.Find Names of Enterprise crewmembers who are in Stellar Cartography:

In this example, we're only looking for the name, so