IS NULL

SQL IS NULL Keyword

The IS NULL condition is used to check whether a column contains a NULL value. This is useful when identifying records that are missing data in certain fields.

SQL IS NULL Syntax

SELECT column1, column2, ...
FROM table_name
WHERE column_name IS NULL;

SELECT column1, column2, ...

FROM table_name

WHERE column_name IS NULL;

SQL IS NULL Patients with No dob Example

This query returns all patients who don’t have a birth date (dob) recorded:

SELECT patient_id, first_name, last_name
FROM Patients
WHERE dob IS NULL;

SELECT patient_id, first_name, last_name

FROM Patients

WHERE dob IS NULL;

SQL IS NULL Labs