Course may include many students Example : Books and Student. Many Books in a Library are issued to many students. Many to Many Relationship Fig . Book Student C++ Kalaivani Manjula Sridevi SQL python The relational model was invented by Edgar Frank Codd (Father of Relational DataBase) as a general model of data, and subsequently promoted by Chris Date and Hugh Darwen among others.
Relational Algebra in DBMS . What is Relational Algebra? Relational Algebra, was first created by Edgar F Codd while at IBM. It was used for modeling the data stored in relational databases and defining queries on it.
Relational Algebra is a procedural query language used to query the database tables using SQL. Relational algebra operations are performed recursively on a relation (table) to yield an output. The output of these operations is a new relation, which might be formed by one or more input relations. Relational Algebra is divided into various groups Unary Relational Operations