The **relational model** for database management is a database model based on first-order predicate logic, first formulated and proposed in 1969 by Edgar F. Codd. In the relational model of a database, all data is represented in terms of tuples, grouped into relations. A database organized in terms of the relational model is a relational database.

The purpose of the relational model is to provide a declarative method for specifying data and queries: users directly state what information the database contains and what information they want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for answering queries.

Most implementations of the relational model use the SQL data definition and query language. A *table* in an SQL database schema corresponds to a predicate variable; the contents of a table to a relation; key constraints, other constraints, and SQL queries correspond to predicates. However, SQL databases, including DB2, deviate from the relational model in many details; Codd fiercely argued against deviations that compromise the original principles.

Read more about Relational Model: Overview, History, Set-theoretic Formulation

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**Relational Model**

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... Codd as part of the

**relational model**, in order to provide a declarative database-query language for this data

**model**... of which the latter, although far less faithful to the original

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**Relational Model**

... The

**relational model**was introduced by E.F ... It is a mathematical

**model**defined in terms of predicate logic and set theory ... The products that are generally referred to as

**relational**databases in fact implement a

**model**that is only an approximation to the mathematical

**model**defined by Codd ...

**Relational Model**

... SQL is a standard

**relational model**language supported by all the

**relational**DBMSs ... SQL was one of the first commercial languages for the

**relational model**... Despite not adhering to the

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“One of the most important things we adults can do for young children is to *model* the kind of person we would like them to be.”

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