[6] 2. (a) Briefly explain the following in the context of transaction management in database systems. i. The lost update problem ii. Two-phase locking protocol iii. Deadlock introduced by locking. (b) The following code creates a view in SQL: CREATE VIEW MyView AS SELECT S1.StoreCode, S1. StoreName, S1. Branch FROM Stores S1 WHERE S1. StoreCode NOT IN (SELECT * FROM Stores S2 WHERE S2.Branch = 'London'>> WITH CHECK OPTION; What is a view, what does the above view do and what do we obtain as results when we perform the following? . SELECT COUNT(*) FROM MyView WHERE Branch = 'Cardiff"; INSERT INTO MyView VALUES ('S100', 'SuperStore', 'London'); [6 (e) The following code creates a trigger in PL/SQL: CREATE TRIGGER Ledger_Auditing BEFORE UPDATE ON Ledger FOR EACH ROW WHEN (:new. Amount/:old. Amount > 1.1) BEGIN INSERT INTO Ledger_Audit VALUES (:old. Quantity, old. Rate, old. Amount); END; What is a trigger, what does the above trigger do, and what happens when we perform the following? UPDATE Ledger SET Amount = Amount * 1.5; [8] please turn over