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Given the following transaction sequence, complete the table by clearly indicati...
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Given the following transaction sequence, complete the table by clearly indicating what locks are present at each of the indicated times (Time 0 to Time 10). Cell entries must have the form S(Tn) - for a shared lock by Tn, X(Tn) - for an exclusive lock by Tn, Tn wait Tm - for a wait of Tn due to Tm (where n and m are transaction numbers)
Time | Transaction | Activity | A | B | C | D |
0 | T1 | READ A |
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1 | T2 | READ B |
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2 | T3 | READ C |
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3 | T1 | READ D |
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4 | T4 | READ B |
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5 | T4 | UPDATE B |
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6 | T3 | UPDATE C |
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7 | T3 | UPDATE A |
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8 | T1 | UPDATE C |
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9 | T2 | READ D |
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10 | T2 | UPDATE A |
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Based on your answers for this lock table, determine if a deadlock is present. Provide the reason you selected your answer.