SYSE.34:8 - Common Anti-Patterns and How to Avoid Them

Misuse	Repair
Read old values, copy them later, then prefer any non-null new field.	Account for intervening writes and establish a maintained correspondence before new-reader reliance.
Make both old and new fields authoritative.	Choose one authority or supply a real conflict-resolution Method.
Repeat the entire migration after a timeout.	Recover committed and partial effects, then apply the qualified replay rule.
Reinstall an old binary after irreversible data loss.	Use a qualified forward repair or information recovery with accepted limits.