3. PGT Computer Science Question Discussion
With regards to the expressive power of the formal relational query languages, which of the following statements is true?
- Relational algebra is more powerful than relational calculus
- Relational algebra has the same power as relational calculus
- Relational algebra has the same power as safe relational calculus
- None of the above
A query can be written in safe Relational Calculus if and only if it can be written in Relational Algebra means it can be written in Relational Calculus as well as Relational Algebra, but Relational calculus also have some unsafe operations and because of those unsafe operations sometimes create ∞(infinite) loop.
So we can say that all safe relational calculus query can be translate into relational algebra
So Option (C) is the correct answer
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