In conservative two phase locking protocol, a transaction
To ensure the serializability, we need two-phase locking protocol (2PL).
2PL has four cases:
In Conservative 2-PL we need to lock all the data items which the transaction required before the transaction starts. And for its conservative nature, this protocol is deadlock free but starvation can occur.
So, the ans. is (D) Should acquire all the locks only at beginning of transaction.
For conservative 2PL should acquire all the locks at the begining and release all the locks at the ending.