Inspect the following logical tables. Construct the likely underlying conceptual model.
1st table
Library Book Loan Event LoanID Date Time
L1 1/21/2010 8:32 L2 1/21/2010 8:37 L3 1/21/2010 8:48
2nd table
Library Book Renewal Event RenewID Date Time
R1 2/7/2010 9:10 R2 2/8/2010 8:20 R3 2/28/2010 12:40
3rd table
Loan-Renewal LoanID RenewID
L1 R1 L1 R3 L3 R2
Serializable Schedule
Consider the three transactions t1 t2 and t3 and the schedules S given below:
T1: r1(x);w1(x);r1(y);w1(y)
T2:r2(z);r2(y);w2(y),r2(x),w2(x)
T3:r3(y);r3(z);w3(y);w3(z)
S:r3(y);r3(z);r1(x);w1(x);w3(y);w3(z);r2(z);r1(y);w1(y);r2(y);w2(y);r2(x);w2(x)
Draw the serializibility (precedence) graph for S . Is the schedule serializable? why or why not? if a schedule is serializable,write down the equivalent serial schedule
