Databases · Middle · Question 52 of 75

What is the hardest part of caching database results?

✓Correct answer: Invalidation: making sure cached data is updated or removed when the source changes
2Choosing a cache key length
3Serializing numbers

Explanation

Common approaches: short TTLs, deleting keys on write, or versioned keys. Always decide how stale the data may be.

Further reading

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