Answer Key: Sharding & Partitioning

Back to Exercises

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Exercise 1: Design Partitioning

Question: Design a partitioning strategy for a user database. What partition key? What strategy?

Answer

Partitioning Strategy: - Partition key: user_id - Strategy: Hash partitioning (even distribution) - Shards: Distribute across shards by hash

Alternative: Range partitioning if range queries needed.

Answer: Hash partitioning on user_id for even distribution, or range partitioning for range queries.

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Exercise 2: Handle Hot Spots

Question: Your partitioned system has hot spots. How do you fix them?

Answer

Solutions: 1. Redesign keys: Add hash component to keys 2. Split shards: Split hot shards 3. Rebalance: Rebalance data across shards

Answer: Redesign keys with hash component, split hot shards, rebalance data.

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Exercise 3: Rebalance Data

Question: How do you rebalance data when adding new shards?

Answer

Rebalancing Process: 1. Add shards: Add new shards 2. Migrate data: Migrate data to new shards 3. Update routing: Update routing to new shards 4. Verify: Verify data distribution

Answer: Add shards, migrate data using consistent hashing, update routing, verify distribution.