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Discussion Forum

Que. 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?
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:S does not have a cascading abort
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