Idempotent SQLite Ledger for Inspection Photo Imports Prevents Duplicate and Silent Overwrites

An inspection team's repeated folder exports can double-count reviews, and a same-named file with different bytes can silently replace an accepted image. The tutorial proposes a small SQLite ledger keyed on job, view and capture identifiers instead of file paths. Each capture is identified by a SHA-256 digest of its original bytes, so byte-identical deliveries are recognized and derived or re-saved images are tracked as separate artifacts. Unseen keys are recorded as new captures, matching keys with identical digests are treated as replays, and mismatched digests are flagged as conflicts that cause the batch to be rejected. The example uses only Python's standard library and synthetic data, and it does not require access to the aircraft itself.