Scaling Reads medium
You build a 'News Feed' by querying the 'Friends' table, then querying the 'Posts' table for each friend. As a user gets more friends, the page gets slower. What is this anti-pattern?
- A The N+1 Query Problem.
- B Deadlock.
- C Index Scan.
- D Sharding.
Answer: A. The N+1 Query Problem.
Fetching a list (1 query) and then fetching details for each item (N queries) creates linear latency growth. It kills database performance.
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