What & Why
The IS NULL operator is used to identify rows where a column has no value; IS NOT NULL identifies rows where it does. NULL means unknown or missing, not zero and not an empty string. IS NULL is how analysts identify incomplete records, active rows, or missing events.
See how it works
Growth wants users who have not churned yet.
SELECT
id,
plan,
created_at
FROM growth.users
WHERE churned_at IS NULL;
Syntax pattern
See explanation
WHERE column_name IS NULL
WHERE column_name IS NOT NULL
- Use IS NULL for missing values.
- Use IS NOT NULL for present values.
- NULL comparisons with = return unknown, not true.
Now You Try
Practice this concept hands-on
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