Scaling Writes easy
Two users try to update the exact same product inventory count at the exact same millisecond. What mechanism does the database use to prevent data corruption?
- A Sharding.
- B Caching.
- C Load Balancing.
- D Locking (Row-level or Table-level).
Answer: D. Locking (Row-level or Table-level).
The database places a 'Lock' on the row for the first user. The second user's request must wait in a queue until the first lock is released. This ensures updates happen sequentially, not simultaneously.
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