Consider the following database schedule with two transactions, T1 and T2. S = r2 (X); r1(X); r2 (Y); w1 (X); r1 (Y); w2 (X); a1; a2 where ri (Z) denotes a read operation by transaction Ti on a variable Z, wi (Z) denotes a write operation by Ti on a variable Z and ai denotes an abort by transaction Ti. Which one of the following statements about the above schedule is TRUE ?

S is recoverable, but has a cascading abort

S does not have a cascading abort

Consider the following database schedule with two transactions, T1 and

1.	Consider the following database schedule with two transactions, T₁ and T₂. S = r₂ (X); r₁(X); r₂ (Y); w₁ (X); r₁ (Y); w₂ (X); a₁; a₂ where r_i (Z) denotes a read operation by transaction T_i on a variable Z, w_i (Z) denotes a write operation by T_i on a variable Z and a_i denotes an abort by transaction T_i. Which one of the following statements about the above schedule is TRUE ?
A.	S is non-recoverable
B.	S is recoverable, but has a cascading abort
C.	S does not have a cascading abort
D.	S is strict
Answer» D. S is strict

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