Category Archives: Без рубрики

Core risk (one sentence) Auto-generated migrations encode what the tool sees, not what the business or production system actually needs. Now the details interviewers expect 👇 1️⃣ Destructive changes sneak in silently (BIGGEST risk) Auto tools often generate things like: … Continue reading →

Core idea (common to all tools) Migration tools ensure order by keeping a metadata table in the database itself. That table records: which migrations ran in what order when with what checksum So ordering is DB-driven, not “file-system magic”. Flyway: … Continue reading →

Scenario: adding a status column with default + app starts writing it Step 1 — Migration V12__add_status.sql Step 2 — App release (same deploy window) New app version starts doing: writes status=’PAID’ | ‘CANCELLED’ queries: WHERE status IN (‘PAID’,’NEW’) Kafka … Continue reading →

Liquibase vs Flyway — Big Picture Aspect Liquibase Flyway Philosophy Declarative, metadata-driven Simple, versioned SQL Learning curve Steeper Very low Migration format XML / YAML / JSON / SQL SQL (primary), Java Rollbacks First-class, explicit Limited (mostly manual) DB-agnostic Strong … Continue reading →

This is a discipline question. Interviewers want to see that you understand what is source of truth vs runtime state. Short interview answer (what to say) “You should never commit migration runtime state or generated artifacts—only migration definitions. That means … Continue reading →

This is usually a practical tooling question. Interviewers want to know whether you’ve actually worked with migrations day-to-day. Short interview answer (safe & senior) “Most popular IDEs support Flyway and Liquibase either natively or via plugins—especially IntelliJ IDEA, DataGrip, Eclipse, … Continue reading →

Short interview answer (30 seconds) “Migration history is shared by treating migrations as code in Git, reviewing them via pull requests, and relying on the database’s schema history tables maintained by tools like Flyway or Liquibase. Additionally, we expose the … Continue reading →

Interview-ready answer (30s) “I prevent data loss by using expand–migrate–contract, making destructive changes a separate, delayed step, validating with preconditions/checks, keeping migrations idempotent and small, taking backups/snapshots before risky steps, and running migrations in staging with production-like data and verification … Continue reading →

Short interview answer (what to say first) “The most common errors are editing applied migrations, running long data updates during deployment, non-idempotent scripts, relying on rollbacks in production, and environment drift caused by manual DB changes.” That alone already signals … Continue reading →

Yes — both Liquibase and Flyway have free versions, but with important differences that interviewers expect you to know. Short interview answer (clean) “Both Liquibase and Flyway are free at the core level. Flyway’s Community Edition covers most common use … Continue reading →