Postgresql easy
PostgreSQL employs Multi-Version Concurrency Control (MVCC). What is a primary functional benefit of this design for concurrent users?
- A It automatically identifies and merges duplicate records during idle CPU cycles.
- B It ensures that read operations do not block write operations, and vice versa.
- C It provides a mechanism for local character set translation at the column level.
- D It prevents the database from growing beyond the physical size of the SSD disk.
Answer: B. It ensures that read operations do not block write operations, and vice versa.
MVCC allows readers to see a consistent snapshot of the data without waiting for writers to finish their transactions. This significantly improves performance under heavy load compared to simple locking.
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