Scaling Reads medium
Unlike a standard SQL View, a Materialized View stores data on disk. When the underlying source tables change, what happens to the Materialized View?
- A It updates instantly via magic.
- B It becomes stale (outdated) until it is explicitly refreshed (e.g., `REFRESH MATERIALIZED VIEW`).
- C It deletes itself.
- D It blocks reads.
Answer: B. It becomes stale (outdated) until it is explicitly refreshed (e.g., `REFRESH MATERIALIZED VIEW`).
This means Materialized Views offer 'Snapshot' consistency, not real-time consistency. They are great for reports, bad for real-time balances.
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