In database theory, relational algebra is a theory that uses algebraic structures for modeling data and defining queries on it with well founded semantics...
51 KB (6,284 words) - 06:52, 22 September 2024
In relational algebra, a projection is a unary operation written as Π a 1 , . . . , a n ( R ) {\displaystyle \Pi _{a_{1},...,a_{n}}(R)} , where R {\displaystyle...
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In relational algebra, a rename is a unary operation written as ρ a / b ( R ) {\displaystyle \rho _{a/b}(R)} where: R is a relation a and b are attribute...
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In relational algebra, a selection (sometimes called a restriction in reference to E.F. Codd's 1970 paper and not, contrary to a popular belief, to avoid...
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database. The relational calculus is similar to the relational algebra, which is also part of the relational model: While the relational calculus is meant...
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A relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970. A database management system used...
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algebraic structures, such as groups, rings, etc. Elementary algebra, i.e. "high-school algebra" Abstract algebra Linear algebra Relational algebra Universal...
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Look up relational in Wiktionary, the free dictionary. Relational may refer to: Relational capital, the value inherent in a company's relationships with...
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(sigma algebra), a refinement of sigma algebras Join (algebraic geometry), a union of lines between two varieties In computing: Join (relational algebra),...
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The relational model (RM) is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in...
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directed graphs, where objects reference each other. Relational is tuples in tables with relational algebra. Tuples are data fields grouped into a "row" with...
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= { x ∈ X : x ∼ a } . {\displaystyle [a]=\{x\in X:x\sim a\}.} In relational algebra, if R ⊆ X × Y {\displaystyle R\subseteq X\times Y} and S ⊆ Y × Z {\displaystyle...
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well as relational algebra) are equivalent in expressive power. Subsequently, query languages for the relational model were called relationally complete...
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the relational algebra projection operation. AS optionally provides an alias for each column or expression in the SELECT list. This is the relational algebra...
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Universal algebra (sometimes called general algebra) is the field of mathematics that studies algebraic structures themselves, not examples ("models")...
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Database normalization (redirect from Relational Database Normalization)
Database normalization is the process of structuring a relational database in accordance with a series of so-called normal forms in order to reduce data...
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Octonion algebra Pre-Lie algebra Poisson algebra Process algebra Quadratic algebra Quaternion algebra Rees algebra Relation algebra Relational algebra Rota–Baxter...
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Relation of degree zero (category Relational algebra)
0-tuple.:56 The zero-degree relations represent true and false in relational algebra.:57 Under the closed-world assumption, an n-ary relation is interpreted...
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operator in mathematics a plane the unary projection operation in relational algebra the Pi function, i.e. the Gamma function when offset to coincide with...
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data Relation (database), a component of a relational database Relational algebra Relational calculus Relational database, a digital database Relationships...
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theoretical properties that larger classes of queries (e.g., the relational algebra queries) do not share. The conjunctive queries are the fragment of...
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SQL (category Relational database management systems)
i.e., with or without an index. Originally based upon relational algebra and tuple relational calculus, SQL consists of many types of statements, which...
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vector onto a straight line Projection (relational algebra), a type of unary operation in relational algebra Projective geometry, the study of geometric...
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various applications in computer science (such as in the theory of relational algebra), philosophy, formal semantics, and evolutionary dynamics. Its foundational...
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Non-associative algebra Outline of algebra Quaternion Rational function Relational algebra Representation theory Root of unity Scheme theory Sigma-algebra Singular...
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NoSQL (redirect from Non-relational database)
NoSQL (originally referring to "non-SQL" or "non-relational") is an approach to database design that focuses on providing a mechanism for storage and retrieval...
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without accessing the stored hierarchy relation". The standard relational algebra and relational calculus, and the SQL operations based on them, are unable...
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into a new table. The operation corresponds to a join operation in relational algebra. Informally, a join stitches two tables and puts on the same row records...
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denoted ρ π {\displaystyle \rho ^{\pi }} The rename operation in relational algebra In economics to represent the discount rate of future pence cash flows...
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Discrete mathematics (section Algebraic structures)
programming; relational algebra used in databases; discrete and finite versions of groups, rings and fields are important in algebraic coding theory;...
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