Syncing and data
Why does a long backfill take a while?
Because Shopify limits how fast any app can read, and a full history can be hundreds of thousands of orders. The backfill uses bulk operations and runs in chunks with backoff, so it is polite to your store and resumable if something interrupts it.
Practically, that means the first sync of a long-lived store is measured in minutes to hours rather than seconds, and it finishes without you watching. Later syncs are incremental and take a fraction of the time, because they only fetch what changed.
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