SnowPro Advanced: Architect · Free practice question 10 of 10
Data quality observability
An Architect wants a Snowflake-native mechanism that runs automatically on a schedule and alerts the team whenever the NULL count in a specific column exceeds a threshold, without adding external monitoring infrastructure. Which feature best satisfies this?
- A.Attach the SNOWFLAKE.CORE.NULL_COUNT data metric function to the column and define an EXPECTATION with the threshold.
- B.Write a stored procedure that queries the column every hour and posts to a Slack webhook if the count is high.
- C.Attach a masking policy that returns NULL when the count is high.
- D.Enable a resource monitor on the loading warehouse.
Show answer and explanation
Correct answer: A. Attach the SNOWFLAKE.CORE.NULL_COUNT data metric function to the column and define an EXPECTATION with the threshold.
Why: Data Metric Functions (DMFs) like NULL_COUNT run on a schedule, and EXPECTATIONs let you declaratively define the threshold — the platform emits events when it's violated. This is the purpose-built Snowflake-native path for column-level data-quality alerting. Custom procedures work but add code and maintenance. Masking policies and resource monitors don't address data-content quality.