relational database

The relational database is the software realization of the concept expressed by the theory introduced by the relational model.

Relational database is the realization of software, which is expressed by the theory introduced by software developers.Relational model.

In relationshipdatabase, Data is stored intable.

Each table contains one or moreColumnTo save specific dataTypes of, Such as strings, numbers, etc.

The collection of tables and all the rules of their related columns are calledSchema.

Each table can be definedconstraintThe data that each row can contain.

Tables can refer to each other, form a relationship, useForeign key.

A kindDatabase management systemIt is the software that realizes the database in the computer system.

Generally, relational databases useSQL languageLet us give instructions for creating a database and define its tablesSchema, Fill the table with data, and finally query the data when needed.

Examples of software implementing relational databases include PostgreSQL, MySQL, SQLite, Oracle, and MicroSoft SQL Server.


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