Question

In data storage, what is the difference between strong consistency and eventual consistency in terms of data replication?

a) Strong consistency ensures data is always up-to-date, while eventual consistency allows for temporary inconsistencies.
b) Strong consistency guarantees that all replicas of the data will be updated immediately, while eventual consistency updates replicas over time.
c) Strong consistency is only used in relational databases, while eventual consistency is used in NoSQL databases.
d) Strong consistency relies on constant communication with all data replicas, while eventual consistency allows some replicas to lag behind.

Answer 1

Strong consistency guarantees immediate updates to all replicas of the data, while eventual consistency allows temporary inconsistencies.

Step-by-step explanation:

The correct answer is b) Strong consistency guarantees that all replicas of the data will be updated immediately, while eventual consistency updates replicas over time.

In data storage, strong consistency ensures that all replicas of the data are always updated immediately and are in sync. This means that when a write operation is performed, the data is replicated to all replicas before the operation is considered complete. On the other hand, eventual consistency allows for temporary inconsistencies between data replicas. With eventual consistency, updates to replicas are not immediately propagated, and it takes time for all replicas to be synchronized.

For example, let's consider a scenario where a user updates their profile information on a social media platform. With strong consistency, the user's information will be immediately replicated and available across all servers, ensuring that all users see the most up-to-date information. However, with eventual consistency, there might be a short period of time where some users see the old information while the replicas are being updated.