Relational Calculus
As Relational Algebra is a procedural query language, Relational Calculus is a non-procedural query language. It basically deals with the end results. It always tells me what to do but never tells me how to do it.
There are two types of Relational Calculus
In-depth articles:
Basic-operators-in-relational-algebra
Extended Relational Algebra Operators
Following are the Previous Year’s Gate Questions
https://www.w3wiki.org/gate-gate-cs-2012-question-50/
https://www.w3wiki.org/gate-gate-cs-2012-question-43/
Introduction of Relational Algebra in DBMS
Pre-Requisite: Relational Model in DBMS
Relational Algebra is a procedural query language. Relational algebra mainly provides a theoretical foundation for relational databases and SQL. The main purpose of using Relational Algebra is to define operators that transform one or more input relations into an output relation. Given that these operators accept relations as input and produce relations as output, they can be combined and used to express potentially complex queries that transform potentially many input relations (whose data are stored in the database) into a single output relation (the query results). As it is pure mathematics, there is no use of English Keywords in Relational Algebra and operators are represented using symbols.