# Data Migration — Manual Review Checklist

## Rollback Plan
- [ ] Rollback script tested and ready before migration
- [ ] Rollback handles partial migration state
- [ ] Rollback is idempotent
- [ ] Database backup taken before migration

## Consistency Verification
- [ ] Migration verification query defined (row count, checksum, sample compare)
- [ ] Old and new data validated before old table dropped
- [ ] Foreign key constraints preserved
- [ ] Indexes migrated or recreated

## Large Table Strategy
- [ ] Batch processing with configurable batch size
- [ ] Migration doesn't lock table for extended period
- [ ] Progress tracking (how many rows processed)
- [ ] Rate limiting to avoid DB overload
- [ ] Dry-run mode tested before actual migration

## Idempotency
- [ ] Migration script is idempotent (can be re-run safely)
- [ ] Uses INSERT ON CONFLICT / INSERT IGNORE / MERGE as appropriate
- [ ] Migration tracks what has been processed (checkpoint table)