Question 90
A production stream aggregates transaction counts for downstream consumption. A production deployment uses Use append output mode for the event stream to address: A query uses a nonaggregating stream and expects append-only emitted records. Which signal should QA check?
Explanation
Correct Answer
Only newly arrived input rows appear in the sink across triggers is the matching outcome for the implemented control (Use append output mode for the event stream) and the stated requirement “A query uses a nonaggregating stream and expects append-only emitted records.”
Incorrect Answers
Every trigger publishes the full current result table pertains to a different control (Use complete output mode where supported for the aggregation) and a different need (A full small aggregation result must be rewritten each trigger and its sink supports that mode). It cannot establish that Use append output mode for the event stream met the stated goal.
New records accumulate exactly once at supported sink boundaries after restart pertains to a different control (Use an append-compatible Delta streaming write with checkpointing) and a different need (A streaming Delta sink must accept new append rows and preserve committed offsets). It cannot establish that Use append output mode for the event stream met the stated goal.
Changes to active group aggregates are emitted on each trigger pertains to a different control (Use update output mode where supported) and a different need (A dashboard needs updated values for incomplete aggregation groups after each microbatch). It cannot establish that Use append output mode for the event stream met the stated goal.