SQL IS NOT NULL

The inverse of IS NULL — keeps only rows where a value actually exists.

What & Why

IS NOT NULL keeps rows where the column genuinely has a value recorded.

BUSINESS QUESTION

Find product feedback rows that contain an NPS score.

id	user_id	feature_id	rating	nps_score	comment	created_at
1	101	1	5	9	Clear and useful	2024-01-25 12:15:00+00
2	102	2	4	NULL	Export worked well	2024-02-20 15:40:00+00
3	103	1	4	7	Helpful setup flow	2024-03-18 09:05:00+00
4	104	3	3	NULL	Needs clearer timing	2024-04-08 17:30:00+00

EXAMPLE QUERY

SELECT id, user_id, nps_score
FROM product.feedback
WHERE nps_score IS NOT NULL;

RESULT

id	user_id	nps_score
1	101	9
3	103	7

Only feedback rows with a known NPS score survive IS NOT NULL.

Now You Try

Product wants features that have a deprecation timestamp so the team can review retired functionality.

Available schema

product

Prefix tables with product.table_name.

nameteamdeprecated_at

product.features

query.sql