Quiz

2667 questions of the kind that actually get asked — in interviews, in architecture review boards, and by the person who has to run the thing at 3 AM. Every answer states the trade-off rather than the slogan, and says when the obvious choice is the wrong one.

All areas2667 Architecture Fundamentals81 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture78 Reliability & Resilience88 Observability81 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication91 Enterprise Architecture91 Legacy Modernization92 AI-Era Architecture86 Software Architecture & Engineering84 Architecture Patterns84 Architecture Decision-Making91 The Architect's Meta-Skills92 Delivery & Release Engineering93 Platform Engineering & Developer Experience92 Testing & Quality Architecture90 Data Platform Architecture88 Streaming & Real-Time Data93 Data Governance & Semantics81 Frontend & Experience Architecture91 Edge, Mobile & IoT88 Regulatory & Data Protection Architecture90 Assurance, Audit & Model Risk88

Difficulty Any beginner intermediate advanced

90 questions in Data Architecture.

Quiz

A neobank stores every account change as an immutable fact rather than a mutable balance. Which needs justify this, how are balances materialised for fast reads, and what happens when a projection is found to be wrong?

A system is event-sourced. A customer exercises their right to erasure. The event log is immutable. How do you comply?

A team wants event sourcing for a new order service, citing audit requirements. What do you recommend?

An organisation wants event sourcing for its order platform because it is considered scalable. What business or audit requirements would actually justify it, and when is CRUD plus an audit log safer?

A query filters on `lower(email)` and there is an index on `email`. The query is slow and the plan shows a sequential scan. Why, and what are the fixes?

A search platform receives continuous document updates while users expect newly published content to appear quickly. How should indexing pipelines, replicas, refresh intervals, cache invalidation and query serving be separated?

A source-code platform must make code across millions of repositories searchable, where repositories differ enormously in size and activity. Which indexing decisions dominate, and what makes this different from indexing documents?

A table has 14 indexes and writes have become slow. How do you decide which to remove?

Prices change continuously based on demand and dates. Search must filter and sort by price over millions of listings. How?

A chat platform stores billions of messages in a wide-column database and hits severe tail-latency problems on hot partitions during large-community activity. Analyse why the storage choice is right but the partitioning is wrong, and what the fix looks like.

A professional network computes "people you may know" from the connection graph. Some accounts have hundreds of thousands of connections. What breaks?

A team needs a store for derived data that is bulk-loaded from offline jobs, updated in real time, and read at very low latency. Why does this workload get its own system rather than reusing the primary online database?