Streams and Tasks Flashcards
7 cards from real SNOWPRO CORE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Streams and Tasks flashcards as text
When using Serverless Tasks in Snowflake, which compute resource handles the execution?
Answer: Snowflake-managed compute that scales automatically based on workload
Serverless Tasks use Snowflake-managed compute resources that scale automatically, so no virtual warehouse needs to be specified or paid for when the task is idle.
Which ACCOUNT_USAGE view provides a full historical record of Snowflake Task execution runs?
Answer: SNOWFLAKE.ACCOUNT_USAGE.TASK_HISTORY
The SNOWFLAKE.ACCOUNT_USAGE.TASK_HISTORY view provides a historical record of task runs including scheduled time, completion time, state (SUCCEEDED/FAILED/SKIPPED), and error messages with up to a 365-day window.
What does the TASK_HISTORY() Information Schema table function return compared to the ACCOUNT_USAGE.TASK_HISTORY view?
Answer: Task runs within the last 7 days with lower latency than ACCOUNT_USAGE
The TASK_HISTORY() Information Schema table function returns task runs within the last 7 days with near-real-time latency, while ACCOUNT_USAGE.TASK_HISTORY has up to a 45-minute delay but covers a 365-day window.
What happens to child tasks in a DAG when the root task is suspended?
Answer: Child tasks are automatically suspended along with the root task
Suspending a root task automatically suspends all child tasks in its DAG because child tasks have no independent schedule — they only run when triggered by their predecessor.
What is the key characteristic of an 'append-only' stream in Snowflake compared to a standard stream?
Answer: It tracks only INSERT operations and ignores UPDATE and DELETE changes
Append-only streams capture only INSERT operations, making them ideal for immutable log-style tables where you only need to process newly appended rows without tracking updates or deletes.
What does the SYSTEM$TASK_DEPENDENTS_ENABLE('') function do in Snowflake?
Answer: Resumes the root task and all of its child tasks in the DAG simultaneously with one call
SYSTEM$TASK_DEPENDENTS_ENABLE() resumes an entire task DAG — the root and all its child tasks — with a single call, providing a convenient alternative to issuing ALTER TASK RESUME for each task individually.
Which practice ensures that stream data in a Snowflake pipeline is processed exactly once without risk of duplication on retry?
Answer: Consuming stream data inside a transaction — the offset advances only if the transaction commits successfully
Stream offsets advance only when the consuming DML transaction commits successfully; if the task fails mid-execution, the stream offset does not advance and the data remains available for the next retry, providing exactly-once semantics.