• Hard Delete: Removes rows permanently from the physical storage layer using DELETE FROM table. Cannot be undone except by restoring database backups.
• Soft Delete: Flags records as deleted without removing them physically, typically using a flag or timestamp column (is_deleted BOOLEAN, deleted_at TIMESTAMP).

Soft Delete Considerations

Soft deletes preserve historical data and support simple record restoration, but require all application queries to include WHERE deleted_at IS NULL filters.