How to retrieve data from relation ‘Professor’ where department name is…
2024
How to retrieve data from relation ‘Professor’ where department name is ‘Mathematics’ and salary is greater than ’65,000’?
- A.
σdept_name = “Mathematics” ⋀ salary>65000 (Professor)
- B.
σ “Mathematics” ⋀ salary>65000 (Professor)
- C.
σdept_name = “Mathematics” and salary>65000 (Professor)
- D.
σ salary>65000 (Professor) ⋀ dept_name = “Mathematics”
Attempted by 229 students.
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Correct answer: A
Ans : A
Solution
The select operation selects tuples that satisfy a given predicate. The lowercase Greek letter sigma (σ) is used to denote selection. The predicate appears as a subscript to (σ). The argument relation is in parentheses after the σ.