Skip to main content

Chapter 21B: Postgres as System of Record Quiz

Twenty questions. No tricks. If you have walked through the eleven lessons and the capstone, you will know these answers. Each question maps to one of the nine drills or one of the SoR habits the chapter taught.

Scoring guidance:

  • 18-20: ready to take the Reconciler database into multi-tenant production
  • 15-17: solid foundation, revisit the lessons where you missed
  • 11-14: redo the capstone before relying on this database at work
  • <=10: rerun the chapter starting at Lesson 0, slowly

Best practice: answer once without notes, then review misses and retake after targeted repair.

What This Quiz Measures

  • O1: System-of-record framing and the gap CRUD leaves behind
  • O2: Migrations as schema history, with safe upgrade and downgrade
  • O3: The runs/turns/tool_calls journal and crash resume reasoning
  • O4: Idempotency keys and ON CONFLICT discipline
  • O5: Concurrency claims with FOR UPDATE SKIP LOCKED and advisory locks
  • O6: The outbox pattern, relay, and dedup_key
  • O7: Append-only events and immutable history
  • O8: RLS policies, roles, tenant isolation, and boundary errors
  • O9: MCP boundary and minimal tool surfaces
  • O10: Forensics from rows alone, four operational queries

Question-to-Outcome Map

QuestionPrimary outcome
Q1O1
Q2O2
Q3O2
Q4O3
Q5O3
Q6O4
Q7O4
Q8O5
Q9O5
Q10O6
Q11O6
Q12O7
Q13O7
Q14O8
Q15O8
Q16O9
Q17O9
Q18O10
Q19O10
Q20Integration
Checking access...