Question
Which of the following is NOT a valid relational algebra
operation?                           ÂSolution
Relational algebra is a theoretical language used for querying and manipulating relations (tables) in a relational database. The key operations in relational algebra are:
- UNION : Combines the results of two queries and returns distinct rows present in either relation.
- INTERSECT : Returns the rows that are present in both relations.
- DIFFERENCE : Returns rows from the first relation that are not in the second relation.
- SELECT : A unary operation that retrieves a subset of rows from a relation based on a condition.
- A, B, C, and E are all valid relational algebra operations, as they represent basic operations to manipulate and retrieve data from relations.
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