Build the indexes that pay for themselves on this query mix.

Each index speeds some queries but costs storage. Total = Σ (weight · query time) + Σ storage built. Indexing everything is a tax on every write.

Practice — no rating pressure. Get as close to the optimum as you can; each play teaches the pattern.

Total cost

3583

query 3583
storage 0

The Index — practice the decision, scored against the optimum

What does the The Index puzzle teach?

Build only the indexes that pay for their storage on the query mix — indexing everything is a tax on every write.

Why do interviews ask about this?

Which indexes to build is the database-design interview — index the queries that earn back their write and storage cost.

How is it scored?

The engine computes the provably-optimal answer for the exact instance you played (dynamic programming, shortest-path, or exhaustive search — never a heuristic) and scores your attempt as a percentage of it. No login needed to see your score.

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Practice0:00

The Index · D4

Build the indexes that pay for themselves on this query mix.

Each index speeds some queries but costs storage. Total = Σ (weight · query time) + Σ storage built. Indexing everything is a tax on every write.

Practice — no rating pressure. Get as close to the optimum as you can; each play teaches the pattern.

Total cost

3583

query 3583
storage 0