| connector stalls | alert on retained WAL bytes and disk headroom |
| event redelivered | versioned idempotent sink |
| schema changes | compatible rollout and quarantine |
| snapshot restarts | resume supported snapshot state |
| hot key | preserve order while scaling other partitions |
| Test connector death during snapshot and streaming, sink lag, schema changes, and TOAST-heavy updates. Reconcile source rows against sink state rather than trusting offsets alone. | |
| ## Test yourself | |
| 1. How can CDC fill the source disk? | |
| 2. What proves no changes were lost? | |
| 3. Why is offset commit alone insufficient? | |
Continue to professional.md. | |