PREVIOUS YEAR SOLVED PAPERS - GATE 2020
- Option : D
- Explanation : d(AB) = d(A) × d(B) d(A + B) ≥ d(A) + d(B) r(A + B) ≤ r(A) + r(B) r(AB) ≠ r(A) r(B)
- Option : A
- Explanation :
To find a number between range [x, y] requires log n comparisons. As, K numbers are to be found, K + log n would be time complexity.
- Option : B
- Explanation : R1: 0x42200000
R2: 0xC1200000
1. Subtract the exponents i.e. divisor exponent from the dividend exponent.
2. Divide the mantissa i.e
3. Sign (opposite sign division result sign is –ve)
Hence, option (B) is correct answer.
39. Consider a schedule of transactions T1 and T2:
| T1 | RA | RC | WD | WB | Commit | |||||
| T2 | RB | WB | RD | WC | Commit |
Here, RX stands for “Read(X)” and WX stands for “Write(X)”. Which one following schedules is conflict equivalent to the above schedule?
- Option : D
- Explanation : R2(B) is conflicting with W1(B) so, W1(B) should always come after R2(B)W2(B) is conflicting with W1(B) similarly, W1(B) should always come after W2(B)R2(D) is conflicting with W1(D), so, W1(D) should always come after R2(D)R1(C) is conflicting with W2(C) so, W2(C) should always come after R1(C)Therefore the transaction will be:
T1 T2 R(B) W(B) R(D) R(A) R(C) W(D) W(B) W(C) Commit Commit
- A
A cell in R holds a set instead of an atomic value.
- B
R has a non-trivial functional dependency X → A, where X is not a superkey and A is a prime attribute
- C
R has a non-trivial functional dependency X → A, where X is not a superkey and A is a non-prime attribute and X is a proper subset of some key.
- D
R has a non-trivial functional dependency X → A, where X is not a superkey and A is a non-prime attribute and X is not a proper subset of any key.
- Option : B
- Explanation : R has a nontrivial functional dependency X → A where X is not a sup and A is a prime attribute.
