Recall & Review
beginner
What is causal consistency in MongoDB?
Causal consistency means that operations that are related in cause and effect order are seen by clients in the same order. It ensures that if one operation depends on another, the dependent operation is always seen after the first.
Click to reveal answer
intermediate
How does causal consistency differ from eventual consistency?
Eventual consistency means updates will be seen eventually but not necessarily in order. Causal consistency guarantees that related updates are seen in the correct order, preserving cause and effect.
Click to reveal answer
beginner
Which MongoDB feature supports causal consistency?
MongoDB supports causal consistency through sessions with causal consistency enabled. This allows clients to read their own writes and maintain operation order.
Click to reveal answer
beginner
Why is causal consistency important in distributed databases?
It helps avoid confusing results by ensuring that operations that depend on each other are seen in the right order, making data easier to understand and trust.
Click to reveal answer
intermediate
What happens if causal consistency is not used in a multi-region MongoDB deployment?
Clients might see updates out of order, causing confusion like reading a reply before the original message or missing intermediate changes.
Click to reveal answer
What does causal consistency guarantee in MongoDB?
✗ Incorrect
Causal consistency ensures that operations that depend on each other are seen in the correct order.
Which MongoDB feature enables causal consistency?
✗ Incorrect
Sessions with causal consistency enabled allow clients to maintain operation order.
What problem can occur without causal consistency in distributed systems?
✗ Incorrect
Without causal consistency, clients may see operations in the wrong order, causing confusion.
Causal consistency is stronger than which consistency model?
✗ Incorrect
Causal consistency is stronger than eventual consistency because it preserves operation order.
In MongoDB, what does enabling causal consistency in a session allow?
✗ Incorrect
It allows clients to read their own writes and maintain the correct order of operations.
Explain causal consistency in MongoDB and why it matters for applications.
Think about how users expect to see their actions reflected in the right order.
You got /3 concepts.
Describe how MongoDB sessions support causal consistency and what happens if it is not used.
Consider the role of sessions in tracking operation order.
You got /3 concepts.