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(t.name = "Codd") — tuple t has a name attribute and its value is "Codd" Book(t) — tuple t is present in relation Book. The formal semantics of such atoms is defined given a database db over S and a tuple variable binding val : V → T D that maps tuple variables to tuples over the domain in S: v.a = w.b is true if and only if val(v)(a ...
QUEL is a relational database query language, based on tuple relational calculus, with some similarities to SQL.It was created as a part of the Ingres DBMS effort at University of California, Berkeley, based on Codd's earlier suggested but not implemented Data Sub-Language ALPHA.
Assuming different domains, i.e., sets of atomic data items from which tuples can be constructed, this query returns different results and thus is clearly not domain independent. Codd's Theorem is notable since it establishes the equivalence of two syntactically quite dissimilar languages: relational algebra is a variable-free language, while ...
The relational calculus is similar to the relational algebra, which is also part of the relational model: While the relational calculus is meant as a declarative language that prescribes no execution order on the subexpressions of a relational calculus expression, the relational algebra is meant as an imperative language: the sub-expressions of ...
Non-standard calculus, an approach to infinitesimal calculus using Robinson's infinitesimals; Calculus of sums and differences (difference operator), also called the finite-difference calculus, a discrete analogue of "calculus" Functional calculus, a way to apply various types of functions to operators; Schubert calculus, a branch of algebraic ...
Tuple relational calculus This page was last edited on 29 August 2020, at 20:28 (UTC). Text is available under the Creative Commons Attribution-ShareAlike 4.0 ...
Join calculus, a theoretical model for the design of distributed programming languages; π-calculus, a formulation of the theory of concurrent, communicating processes, that was invented by Robin Milner; Relational calculus, a calculus for the relational data model Domain relational calculus; Tuple calculus, inspired the SQL language
Multi-index notation is a mathematical notation that simplifies formulas used in multivariable calculus, partial differential equations and the theory of distributions, by generalising the concept of an integer index to an ordered tuple of indices.