Oracle Database 12c: Installation and Administration — Question 172

The HR user updates the salary of one of the employees in the non-partitioned EMPLOYEES table, but does not commit the transaction.
Which two types of lock exist in this situation? (Choose two.)

Answer options

• A. exclusive lock on the EMPLOYEES table
• B. null lock on the row being updated
• C. null lock on the EMPLOYEES table
• D. row level lock on the row being updated
• E. shared lock on the EMPLOYEES table

Correct answer: D, E

Explanation

In this case, a row level lock is placed on the specific row being updated to prevent other transactions from accessing it until the transaction is committed. Additionally, a shared lock exists on the EMPLOYEES table to allow other transactions to read data while preventing modifications to the table structure until the transaction is complete. The other options are incorrect as they either do not reflect the lock types applicable in this scenario or mischaracterize the state of the locks.