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SQL IS NULL Keyword Usage and Example

SQL Keyword Reference

IS NULL

The IS NULL command is used to test for null values (NULL values).

The following SQL lists the "Address" Customers with NULL values in the field:

Example

SELECT CustomerName, ContactName, Address
FROM Customers
WHERE Address IS NULL;

Note: NULL values are different from zero values or fields containing spaces. Fields with NULL values are fields left blank during the record creation process!

Hint:Always use IS NULL to find NULL values.

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