Apply a new Margins book catalog to an environment's database.
The link's token is used once for the download and never shown again.
No runs yet.
What this tool does: Margins sends us a full book catalog (~2.7 million books) every few weeks. This tool downloads it, compares it with the last catalog we applied, and writes only the differences into the selected environment's database.
Dry run downloads and compares but changes nothing — use it first to sanity-check a new link.
Catalog changes = what Margins changed since our baseline: new books, updated books, and books removed from their catalog (we detect removals but never delete from our database).
Database impact = what actually happened in our database: books before → after the run, rows inserted (brand new), updated (we had them, data changed), enriched (we had better data from another vendor; only missing fields were filled in).
Baseline = the catalog snapshot this environment's database currently reflects. It only moves forward when a run finishes cleanly, so a failed run can simply be retried.
If a run says FAILED: read its error line — an expired Margins link just needs a fresh link (or pick "previously processed catalog"). If it says errors during ingest, the baseline did NOT move; re-run after engineering takes a look. LOST means the worker died (rerun is safe). A run can always be cancelled and re-submitted — re-running the same catalog is harmless.
You are asserting that this environment's database already holds that catalog snapshot. Future deltas are computed against it.