Exercise 16.3 Consider a database with objects X and Y and assume that there are two transactions Tl and T2. Transaction T1 reads objects X and Y and then writes object X. Transaction T2 reads objects X  and Y  and then writes objects X  and Y.

 

1.     Give an example schedule with actions of transactions T1 and T2 on objects X and Y

that  results  in  a  write-read conflict.

2.     Give an example schedule with actions of transactions T1 and T2 on objects X and Y

that  results  in  a  read-write conflict.

3.     Give an example schedule with actions of transactions T1 and T2 on objects X and Y

that  results  in  a  write-write conflict.

4.     For each of the three schedules, show that Strict 2PL disallows the schedule.