Choose any four relational algebra operators and explain how each functions.
What will be an ideal response?
For example: Select – produces a horizontal subset of a relation. Project produces a vertical subset
of a relation by picking out particular attributes. Product (Cartesian product) produces a result
relation by multiplying one relation by another. If the first relation contained 20 rows and the
second 50, the result relation would contain 20 × 50 rows. Join produces a result relation by
(commonly) joining two relations over the equal value of an attribute common to both relations.
Examples should be given for all operators explained.
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What will be an ideal response?