Scaling Reads medium
You denormalize your schema by storing `User_Name` inside the `Comments` table to avoid joins. What is the new maintenance burden?
- A Queries become slower.
- B You must execute a 'Write Fan-Out': When a user changes their name, you must find and update every single comment they ever wrote.
- C The table size decreases.
- D You cannot use indexes.
Answer: B. You must execute a 'Write Fan-Out': When a user changes their name, you must find and update every single comment they ever wrote.
Denormalization speeds up Reads but complicates Writes (Update Anomalies). You trade CPU time (JOINS) for Write complexity.
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