Code RoomMulti-tenant order secondary indexes
HardPrep Room Coding #3152

Multi-tenant order secondary indexes

System designDatabases & SQLDistributed systemsSenior–Staff~45 min

Design secondary indexing for a multi-tenant e-commerce order store that is primary-keyed and partitioned by (tenant_id, order_id). Merchants need to query orders by customer_email, by status, and by a date range — none of which is the partition key — across potentially millions of orders per large tenant, with p95 under 150ms. The store does ~80k order writes/sec globally. Compare global vs local secondary indexes for this access pattern, pick one (or a mix), and explain the consistency and write-cost trade-offs.

What a strong answer looks like

Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.

Clarify5:00 left
Estimate5:00 planned
Design15:00 planned
Deep dive12:00 planned
Failure8:00 planned
0:00
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.