Database Management Systems · Query languages

Relational algebra

The formal, math-like operations SQL actually compiles down to under the hood.

Also known as: relational calculus, formal query languages.

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• Relational model: Data as tables of rows and columns, with no other structure implied.

Related topics

• SQL filtering and projection: Picking which rows and columns you want back with SELECT and WHERE.
• Query processing and optimization: How the database decides which order to run joins and filters in, to answer a query as cheaply as possible.