jargon

Data engineering·Moving data out of the source

before the change feed is any use you have to copy the table as it stands today, while it is still being written to.

Initial snapshot

Also calledseed load, bootstrap snapshot, backfill snapshot

The one-off full copy that gives a change feed something to apply changes to. The interesting part is the handover: rows are being modified while the snapshot is running, so the snapshot and the stream overlap, and the standard resolution is to start capturing the log first and let idempotent upserts settle the overlap. Getting the handover wrong produces a table that is right on average and wrong for exactly the rows that were busy.

Commonly confused with