Question
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
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Q. 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...
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