Cianplan

Level 6: Applied: cases, FDE scenarios, mocks · L6.2 Classic cases II

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Choose fan-out on write vs read and handle celebrities.

15 min · Pro

What you take away

  • Fan-out on write makes a read one key-value lookup and turns each post into as many writes as the author has followers.

And 3 more inside the class, in Pro.

How the class is laid out

  1. The prompt
  2. Requirements and the numbers
  3. The design
  4. Three decisions
  5. The twist
  6. Check your understanding