I assume that you know the basic terms used in relational databases. Selection operator operates on the rows from a relation. Basic operators in relational algebra . Questions from Previous year GATE question papers. Relational algebra is a family of algebras with a well-founded semantics used for modelling the data stored in relational databases, and defining queries on it. Write the following queries using relational algebra. Select. Auflage, 1999. Auflage, 2001. There may be multiple solutions to the same query. There are 5 different types of Basic Operators in Relational Algebra in DBMS,. The relational algebra calculator helps you learn relational algebra (RelAlg) by executing it. It is denoted by sigma (σ). It would be much clearer to use a simple comparison such as "birthdate