Workspace System Design
Learning pathsA
COURSE CHECKPOINT · 5 QUESTIONS

Quiz: Database Indexing

Apply Database Indexing to concrete decisions. Choose an answer for every question, then review the explanations.

Visual checkpoint

Use this diagram to locate the state and failure boundaries tested by the questions. Answer all five questions before revealing feedback; the result is a study checkpoint rather than a certification.

Query tenant + cursor → B-tree root (seek); B-tree root → Tenant range (narrow); Tenant range → Recent failed keys (ordered scan); Recent failed keys → Table rows (fetch if needed); Table rows → 50 results (limit)
Scroll to inspect the diagram, or open it at full size.

Figure — Query tenant + cursor → B-tree root (seek); B-tree root → Tenant range (narrow); Tenant range → Recent failed keys (ordered scan); Recent failed keys → Table rows (fetch if needed); Table rows → 50 results (limit)

Review your reasoning

After checking answers, identify the incorrect assumption behind each missed question. Rewrite it as a rule with a concrete exception or failure case, then return to the lesson.

Why might a status-only index be ignored when nearly every record is active?

1. Why can a status-only index be unhelpful when nearly all rows are active?
2. A tenant query filters failures and orders newest first. Which index is most aligned?
3. What is the recurring cost of another index?
4. What caution applies to EXPLAIN ANALYZE?
5. Why add an ID to a timestamp pagination key?

Answers and your latest score are saved to your account when you check them. Completion records your attempt, not a passing certification.