Final answer:
The statement about deadlocks and shared locks is false. Deadlocks occur when multiple transactions wait for each other to release locks without any willing to do so, leading to a standstill.
Step-by-step explanation:
The statement that a deadlock occurs when two users hold shared locks on portions of a table that are needed to complete the transaction of the other user is false
A deadlock typically occurs in a database when two or more transactions are waiting for each other to release locks, without a transaction willing to release its lock. Consider this example where Transaction 1 has a lock on Resource A and needs to lock Resource B to complete, but Transaction 2 has a lock on Resource B and needs to lock Resource A to complete. Neither transaction can proceed, and a deadlock occurs.