jargon

Data engineering·Moving data out of the source

the row was committed in the source at 09:00 and appeared in the warehouse at 09:41, and nobody could say which hop ate the forty minutes.

Ingestion lag

Also calledpipeline lag, end-to-end lag, data latency

The delay between a change happening in the source and it being queryable at the destination. It is the number the business actually feels, and it is a sum over every hop, so it can only be diagnosed if each stage stamps its own arrival time. Measuring it end to end rather than per component is the difference between 'the pipeline is slow' and 'the connector is fine, the merge step waits for a lock'.

Commonly confused with