02 Analyze and design — instructor notes
Guide the worksheet, query translation, and architecture decision record without revealing the model too early.
Timing
Use three blocks: 30 minutes for source inspection, 20 minutes for query translation, and 30 minutes for the ADR. Pair review is more valuable than shortening the ADR.
Teaching points
- Start from query patterns, then choose
ORDER BY; do not copy Elasticsearch mappings column for column. - Distinguish OTel resource, span, and log attributes before deciding what to promote from
Map. - ClickHouse Cloud object storage removes the hot/warm/cold node-tier decision; TTL still owns deletion.
- A dual-write window proves the new pipeline with live data and preserves a rollback path.
Answer discipline
Keep the reference answers closed until all three learner artifacts contain a defensible attempt. Accept decisions that differ from the model when the learner names the trade-off and a validation plan.
Hard checkpoint
The worksheet, five query translations, and all seven ADR decisions are complete. The learner can explain why the sort key and schema follow access patterns.