Which of the following terms means that the data used during the execution of a transaction cannot be used by a second transaction until the first one is completed ?

The correct answer is option 4: Isolation

Key Points

• Isolation is one of the four ACID properties (Atomicity, Consistency, Isolation, Durability) of database transactions.
• It ensures that the intermediate state of a transaction is invisible to other concurrent transactions.
• This means that:
  • No other transaction can access or modify data being used by a currently executing transaction.
  • Each transaction is executed as if it were the only transaction in the system.

Additional Information

• Consistency: Ensures that a transaction brings the database from one valid state to another.
• Atomicity: Ensures that either all operations of a transaction are completed or none are.
• Durability: Guarantees that once a transaction is committed, its changes are permanent even in case of a system failure.

Hence, the correct answer is: option 4: Isolation