Cassandra easy
Why is Cassandra famously capable of handling extremely high 'Write' throughput compared to traditional relational databases?
- A It writes data into an in-memory 'Memtable' and sequentially appends it to a 'Commit Log' on disk, avoiding expensive random disk seeks.
- B It stores all data in a compressed ZIP format that makes disk writes 10x faster.
- C It only writes data to the disk once a week during a maintenance window.
- D It skips the CPU processing and writes raw electrical signals directly to the storage controller.
Answer: A. It writes data into an in-memory 'Memtable' and sequentially appends it to a 'Commit Log' on disk, avoiding expensive random disk seeks.
Cassandra uses a Log-Structured Merge (LSM) Tree. Unlike B-Trees which require random disk I/O to update data 'In-Place', LSM Trees turn every write into a fast, sequential append. This makes Cassandra ideal for high-velocity data like logs, metrics, or IoT streams.
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