A Data Engineer needs to monitor the quality of hr.tables.employee_dim using a Data Metric Function (DMF). Which DMF will return the percent of NULL values for the passport column in table…

Question

Options

• ASELECT SNOWFLAKE.CORE.NULL_COUNT(SELECT passport FROM
• BSELECT SNOWFLAKE.CORE.AVG(SELECT passport FROM hr.tables.employee_dim);
• CSELECT SNOWFLAKE.CORE.BLANK_COUNT(SELECT passport FROM
• DSELECT SNOWFLAKE.CORE.NULL_PERCENT(SELECT passport FROM

• A
  5% (1)
• B
  5% (1)
• D
  89% (17)

Explanation

SNOWFLAKE.CORE.NULL_PERCENT is the correct built-in DMF for this task - it accepts a table reference and column, then returns the percentage of NULL values, which is exactly what the question asks for.

Why the distractors fail:

• A (NULL_COUNT) returns the raw count of NULLs, not a percentage - a different metric entirely.
• B (AVG) computes the average of numeric values and has no relevance to NULL detection; it's a distractor borrowing from standard SQL aggregate functions.
• C (BLANK_COUNT) does not exist as a Snowflake DMF - it conflates "blank" (empty string) with NULL, which are distinct concepts in SQL.

Memory tip: Match the function name to the output unit - if the question asks for a percent, the function must end in _PERCENT. Snowflake's DMF naming is intentionally descriptive: NULL_COUNT → a count, NULL_PERCENT → a percentage.

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