Problem 1. Determine whether each of the following schedules is conict-serializable
and explain why. If conict-serializable show the steps of _nding an equivalent serial schedule. In the schedules ri(X) and wj(Y ) represent read(X) issued by transaction Ti and write(Y ) issued
by transaction Tj respectively.
r1(A);w2(A); r3(A);w1(A);
(b) w1(A); r2(A);w2(B); r3(B); r1(C);w3(C);
Problem 2. For each of the following provide a transaction schedule that satisfies all
the specified properties and explain why:
not view-serializable; recoverable; not cascadeless
view-serializable; not conict-serializable; not recoverable
Problem 3. Consider a timestamp-based concurrency control manager that assigns
timestamps to transactions in the order of their starts. In the following sti means that transaction
Ti starts and coi means Ti commits. In each case below explain what action the concurrency
control manager will perform for the last write request.
st1; st2; st3; r2(A);w1(B); co2;w3(B)
st1; st2;w1(A); r2(B); co2;w1(B)
Problem 4. Assume a database that crashed during execution. Based on the following
log answer each of the questions below:

*crash*
(a) Show the steps of the REDO pass.
(b) Show the steps of the UNDO pass.
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