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Relational database

Index Relational database

A relational database is a digital database based on the relational model of data, as proposed by E. F. Codd in 1970. [1]

65 relations: Abstraction layer, ACID, Application programming interface, Attribute (computing), B+ tree, Bitmap index, Boolean data type, Business logic, Business rule, Candidate key, Cartesian product, Check constraint, Codd's 12 rules, Column (database), Communications of the ACM, Complement (set theory), Compound key, Data verification, Database, Declarative programming, Distributed Data Management Architecture, Domain of a function, DRDA, Edgar F. Codd, Foreign key, Hierarchical database model, IBM Research - Almaden, Index (publishing), Intersection (set theory), Join (SQL), Many-to-many (data model), Morgan Kaufmann Publishers, Natural key, Network model, One-to-many (data model), One-to-one (data model), Primary key, Procedural programming, Projection (relational algebra), Query language, R-tree, Record (computer science), Relation (database), Relational algebra, Relational calculus, Relational database management system, Relational model, Relvar, Result set, Row (database), ..., Select (SQL), Set operations (SQL), Set theory, SQL, Stored procedure, Subset, Superkey, Surrogate key, Table (database), Tandem Computers, Tuple, Union (set theory), Universally unique identifier, View (SQL), Where (SQL). Expand index (15 more) »

Abstraction layer

In computing, an abstraction layer or abstraction level is a way of hiding the implementation details of a particular set of functionality, allowing the separation of concerns to facilitate interoperability and platform independence.

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In computer science, ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties of database transactions intended to guarantee validity even in the event of errors, power failures, etc.

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Application programming interface

In computer programming, an application programming interface (API) is a set of subroutine definitions, protocols, and tools for building software.

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Attribute (computing)

In computing, an attribute is a specification that defines a property of an object, element, or file.

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B+ tree

A B+ tree is an N-ary tree with a variable but often large number of children per node.

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Bitmap index

A bitmap index is a special kind of database index that uses bitmaps.

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Boolean data type

In computer science, the Boolean data type is a data type that has one of two possible values (usually denoted true and false), intended to represent the two truth values of logic and Boolean algebra.

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Business logic

In computer software, business logic or domain logic is the part of the program that encodes the real-world business rules that determine how data can be created, stored, and changed.

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Business rule

A business rule is a rule that defines or constrains some aspect of business and always resolves to either true or false.

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Candidate key

In the relational model of databases, a candidate key of a relation is a minimal superkey for that relation; that is, a set of attributes such that.

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Cartesian product

In set theory (and, usually, in other parts of mathematics), a Cartesian product is a mathematical operation that returns a set (or product set or simply product) from multiple sets.

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Check constraint

A check constraint is a type of integrity constraint in SQL which specifies a requirement that must be met by each row in a database table.

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Codd's 12 rules

Codd's twelve rules are a set of thirteen rules (numbered zero to twelve) proposed by Edgar F. Codd, a pioneer of the relational model for databases, designed to define what is required from a database management system in order for it to be considered relational, i.e., a relational database management system (RDBMS).

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Column (database)

In a relational database, a column is a set of data values of a particular simple type, one value for each row of the database.

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Communications of the ACM

Communications of the ACM is the monthly journal of the Association for Computing Machinery (ACM).

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Complement (set theory)

In set theory, the complement of a set refers to elements not in.

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Compound key

In database design, a composite key is a candidate key that consists of two or more attributes (table columns) that uniquely identify an entity occurrence (table row).

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Data verification

Data verification is a process in which different types of data are checked for accuracy and inconsistencies after data migration is done.

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A database is an organized collection of data, stored and accessed electronically.

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Declarative programming

In computer science, declarative programming is a programming paradigm—a style of building the structure and elements of computer programs—that expresses the logic of a computation without describing its control flow.

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Distributed Data Management Architecture

Distributed Data Management Architecture (DDM) is IBM's open, published software architecture for creating, managing and accessing data on a remote computer.

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Domain of a function

In mathematics, and more specifically in naive set theory, the domain of definition (or simply the domain) of a function is the set of "input" or argument values for which the function is defined.

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Distributed Relational Database Architecture (DRDA) is a database interoperability standard from The Open Group.

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Edgar F. Codd

Edgar Frank "Ted" Codd (19 August 1923 – 18 April 2003) was an English computer scientist who, while working for IBM, invented the relational model for database management, the theoretical basis for relational databases and relational database management systems.

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Foreign key

In the context of relational databases, a foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another table or the same table.

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Hierarchical database model

A hierarchical database model is a data model in which the data is organized into a tree-like structure.

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IBM Research - Almaden

IBM Research - Almaden is in Almaden Valley, San Jose, California, and is one of IBM's twelve worldwide research labs that form IBM Research.

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Index (publishing)

An index (plural: usually indexes, more rarely indices; see below) is a list of words or phrases ('headings') and associated pointers ('locators') to where useful material relating to that heading can be found in a document or collection of documents.

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Intersection (set theory)

In mathematics, the intersection A ∩ B of two sets A and B is the set that contains all elements of A that also belong to B (or equivalently, all elements of B that also belong to A), but no other elements.

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Join (SQL)

An SQL join clause combines columns from one or more tables in a relational database.

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Many-to-many (data model)

In systems analysis, a many-to-many relationship is a type of cardinality that refers to the relationship between two entities A and B in which A may contain a parent instance for which there are many children in B and vice versa.

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Morgan Kaufmann Publishers

Morgan Kaufmann Publishers is a Burlington, Massachusetts (San Francisco, California until 2008) based publisher specializing in computer science and engineering content.

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Natural key

A natural key (also known as business key) is a type of unique key, found in relational model database design, that is formed of attributes that already exist in the real world.

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Network model

The network model is a database model conceived as a flexible way of representing objects and their relationships.

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One-to-many (data model)

In systems analysis, a one-to-many relationship is a type of cardinality that refers to the relationship between two entities (see also entity–relationship model) A and B in which an element of A may be linked to many elements of B, but a member of B is linked to only one element of A. For instance, think of A as books, and B as pages.

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One-to-one (data model)

In systems analysis, a one-to-one relationship is a type of cardinality that refers to the relationship between two entities (see also entity–relationship model) A and B in which one element of A may only be linked to one element of B, and vice versa.

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Primary key

In the relational model of databases, a primary key is a specific choice of a minimal set of attributes (columns) that uniquely specify a tuple (row) in a relation (table).

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Procedural programming

Procedural programming is a programming paradigm, derived from structured programming, based upon the concept of the procedure call.

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Projection (relational algebra)

In relational algebra, a projection is a unary operation written as \Pi_(R) where a_1,...,a_n is a set of attribute names.

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Query language

Query languages or data query languages (DQLs) are computer languages used to make queries in databases and information systems.

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R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons.

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Record (computer science)

In computer science, a record (also called a structure, struct, or compound data) is a basic data structure.

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Relation (database)

In relational database theory, a relation, as originally defined by E. F. Codd, is a set of tuples (d1, d2,..., dn), where each element dj is a member of Dj, a data domain.

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Relational algebra

Relational algebra, first created by Edgar F. Codd while at IBM, is a family of algebras with a well-founded semantics used for modelling the data stored in relational databases, and defining queries on it.

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Relational calculus

Relational calculus consists of two calculi, the tuple relational calculus and the domain relational calculus, that are part of the relational model for databases and provide a declarative way to specify database queries.

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Relational database management system

A relational database management system (RDBMS) is a database management system (DBMS) based on the relational model invented by Edgar F. Codd at IBM's San Jose Research Laboratory.

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Relational model

The relational model (RM) for database management is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in 1969 by Edgar F. Codd, where all data is represented in terms of tuples, grouped into relations.

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In relational databases, relvar is a term introduced by C. J. Date and Hugh Darwen as an abbreviation for relation variable in their 1995 paper The Third Manifesto, to avoid the confusion sometimes arising from the use of the term relation, by the inventor of the relational model, E. F. Codd, for a variable to which a relation is assigned as well as for the relation itself.

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Result set

A SQL result set is a set of rows from a database, as well as metadata about the query such as the column names, and the types and sizes of each column.

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Row (database)

In the context of a relational database, a row—also called a tuple—represents a single, implicitly structured data item in a table.

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Select (SQL)

The SQL SELECT statement returns a result set of records from one or more tables.

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Set operations (SQL)

Set operations allow the results of multiple queries to be combined into a single result set.

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Set theory

Set theory is a branch of mathematical logic that studies sets, which informally are collections of objects.

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SQL (S-Q-L, "sequel"; Structured Query Language) is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS).

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Stored procedure

A stored procedure (also termed proc, storp, sproc, StoPro, StoredProc, StoreProc, sp, or SP) is a subroutine available to applications that access a relational database management system (RDBMS).

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In mathematics, a set A is a subset of a set B, or equivalently B is a superset of A, if A is "contained" inside B, that is, all elements of A are also elements of B. A and B may coincide.

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A superkey or super-key is defined in the relational model of database organization as a set of attributes of a relation variable for which it holds that in all relations assigned to that variable, there are no two distinct tuples (rows) that have the same values for the attributes in this set.

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Surrogate key

A surrogate key (or synthetic key, entity identifier, system-generated key, database sequence number, factless key, technical key, or arbitrary unique identifier) in a database is a unique identifier for either an entity in the modeled world or an object in the database.

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Table (database)

A table is a collection of related data held in a structured format within a database.

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Tandem Computers

Tandem Computers, Inc. was the dominant manufacturer of fault-tolerant computer systems for ATM networks, banks, stock exchanges, telephone switching centers, and other similar commercial transaction processing applications requiring maximum uptime and zero data loss.

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In mathematics, a tuple is a finite ordered list (sequence) of elements.

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Union (set theory)

In set theory, the union (denoted by ∪) of a collection of sets is the set of all elements in the collection.

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Universally unique identifier

A universally unique identifier (UUID) is a 128-bit number used to identify information in computer systems.

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View (SQL)

In a database, a view is the result set of a stored query on the data, which the database users can query just as they would in a persistent database collection object.

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Where (SQL)

A WHERE clause in SQL specifies that a SQL Data Manipulation Language (DML) statement should only affect rows that meet specified criteria.

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Constraint (database), Database constraint, Database constraints, Database relational, Relational DB, Relational Database, Relational Databases, Relational databases, Relational instance, Relational query.


[1] https://en.wikipedia.org/wiki/Relational_database

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