3. When interviewing at Oracle, they tell you that they use a transaction management system that...

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3. When interviewing at Oracle, they tell you that they use a transaction management system that assigns unique words as ids to to objects, where the words are dictionary words (Oxford English dictionary only). The system uses exclusive locking of objects for concurrency control. The system restricts transactions to acquire locks only in lexicographically decreasing order of object id (i.e., if a word appears later in the dictionary it has a higher object id, and it will be locked first). They tell you that this system will not deadlock only if all locks are acquired at the start of the transaction. You think otherwise, and say that even if you acquire locks during the transaction (obeying the decreasing lexicographic rule), there will be no deadlocks. Who is right? Give an example or present a proof, as applicable. You can assume 2 phase locking for this problem. 3. When interviewing at Oracle, they tell you that they use a transaction management system that assigns unique words as ids to to objects, where the words are dictionary words (Oxford English dictionary only). The system uses exclusive locking of objects for concurrency control. The system restricts transactions to acquire locks only in lexicographically decreasing order of object id (i.e., if a word appears later in the dictionary it has a higher object id, and it will be locked first). They tell you that this system will not deadlock only if all locks are acquired at the start of the transaction. You think otherwise, and say that even if you acquire locks during the transaction (obeying the decreasing lexicographic rule), there will be no deadlocks. Who is right? Give an example or present a proof, as applicable. You can assume 2 phase locking for this problem.