Which of the following is NOT an operation in relational algebra?

Which of the following is NOT an operation in relational algebra?SelectionProjectionInsertionJoinNext

Relational Algebra is a __________ query language that takes two relations as input and produces another relation as an output of the query.a.Fundamentalb.Relationalc.Structurald.Procedural

Which of the following is used to denote the selection operation in relational algebra?a.Lambda (Greek)b.Sigma (Greek)c.Omega (Greek)d.Pi (Greek)

All relational operators always take one relation as the input and output another relation.Question 2Select one:TrueFalse

What does the projection operation in relational algebra do?a.Produces a new relation containing tuples that appear in both input relationsb.Retrieves specific rows from a relationc.Retrieves specific columns from a relationd.Combines tuples from two relations based on a common attribute