SkillCoded

CI/CD

Database Changes and Backward Compatibility

Deliver database changes as versioned migrations that preserve backward compatibility across application versions and delay destructive cleanup until evidence permits it.

Intermediate14 min read
CI/CD lessonDelivery and reliability foundationsPractice

UNTIMED COACHING

Practice before the pressure

Use feedback to correct the model, not merely memorize an option position.

GUIDED PRACTICE

Practice the lesson questions

Answer normal lesson questions without a timer. Every answer includes an explanation, and incorrect answers can be tried again before continuing.

CONCEPT MODELS

See the lesson as a system

Use these visual guides to connect the key ideas before answering the questions.

Connect the roles in Database Changes and Backward CompatibilityKeep migration script, expansion state, compatible service, and data transition as separate service roles.
Connect the roles in Database Changes and Backward CompatibilityA topic-specific model connects four distinct roles used to reason about database changes and backward compatibility.
Migration commandCommand versions one schema change
Schema dataData supports old and new application fields
Running serviceService reads old and new schema safely
Migration processProcess copies values into new fields
Verify Removal gateConnect removal gate with its topic-specific inspection, expected outcome, and protected delivery boundary.
Verify Removal gateA verification model for database changes and backward compatibility connects the final service decision to its check, result, and protected boundary.
Cleanup decisionDecision waits for compatibility evidence
Starting checkInspect cleanup decision
Expected resultConfirm cleanup decision
Safety boundaryProtect migration command scope