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Definition: Relational Database Model
The‘relational database model’ allows defining data structures, storing and retrieving entities. In the relational database model, the data and relations between them are organized into tables. The model is attributed to be developed by E F Codd.
Data is generally presented as a collection of relations, with each relation depicted as a table.The model structures data using relations, which are grid like mathematical structures i.e. tables, consisting of columns and rows.Each row consists of a separate entity, whereas each column is populated by the attributes of each of the entities. Every table has a set of attributes that taken together as a ‘key’ or ‘super key’ uniquely identifies each entity. In other words,each relation has a header and body. The ‘header’being the list of columns;and the ‘body’being the set of data organised in rows (attributes) that actually describes the relation.
Besides defining how the data is structured, the relational model also lays down a set of rules called ‘integrity constraints’ to enforce data integrity. Additionally, the model defines a special aspect called as ‘normalization’ to maintain efficient data storage.