Question: Why is it considered a good best practice to exclude NULL user_id values from reach and frequency queries?
- Because NULL user_id values are deemed invalid traffic in post-impression server-side models.
- This would be redundant; records with NULL user_id values have been removed upstream of query processing anyway.
- Reach and frequency cannot be accurately determined for NULL user_id values, so this group is excluded to prevent NULL user_id values from skewing the results.
The answer(s) to the question is highlighted in the BOLD text above. You can also find more questions and answers related to the exams on the “Amazon Marketing Cloud Certification” page.
