What do you understand by RDBMS?
Relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as invented by E...

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Relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as invented by E. F. Codd, of IBM's San Jose Research Laboratory. Relational database is a collection of tables of data all of which are formally described and organized according to the relational model.