Relational database is a database based on the relational model. It uses mathematical concepts and methods such as set algebra to process data in the database. Various entities in the real world and various connections between entities are Represented using a relational model.
The relational model was first proposed by Edgar Codd in 1970, in conjunction with the "Codd's Twelve Laws". Today, although there are some criticisms of this model, it remains the traditional standard for data storage.
The standard data query language SQL is a language based on a relational database. This language performs retrieval and operation of data in a relational database. The relational model consists of three parts: relational data structure, relational operation set, and relational integrity constraints.
Simply put, a relational database is a database composed of multiple two-dimensional row and column tables that can be connected to each other.
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