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Relational Databases

Relational databases are, well... a collection of data items that have relations between them. These relations are made by associating a one table's primary key with another table's foreign key. It is a great advancement from the old long table that was used to store data which was inefficient in terms of search, memory and space.  And as for normalization; it means a process in which tables are structured to eliminate redundancy and repetition among data and the CRUD operations side-effects. And as a direct result we improve the performance of our queries. An example of a relational database would be two tables; one for student and the other for school. Both of these tables have a column for the school id, and so we make a connection between by assigning the first one as a primary key and the other as foreign key.

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