COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Union
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Set-difference
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Difference
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Intersection
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Detailed explanation-1: –the operation denoted by-allows for finding tuples that are in one relation but are not in another.
Detailed explanation-2: -Explanation: The expression r − s produces a relation containing those tuples in r but not in s.
Detailed explanation-3: -Explanation: The select operation selects tuples that satisfy a given predicate.
Detailed explanation-4: -Union (∪) Union operation is done by Union Operator which is represented by “union"(∪). It is the same as the union operator from set theory, i.e., it selects all tuples from both relations but with the exception that for the union of two relations/tables both relations must have the same set of Attributes.
Detailed explanation-5: -Explanation: Join finds the common tuple in the relations and combines it.