In this guide we will explain how to use the MySQL IS NOT NULL condition with syntax and examples.
Description
The IS NOT NULL condition is used to test for a NOT NULL value in a SELECT, INSERT, UPDATE, or DELETE statement.
Syntax
The syntax for the IS NOT NULL Condition is:
expression IS NOT NULL
Parameters or Arguments
expressionThe value to test if it is a not NULL value.
Note
- If expression is NOT a NULL value, the condition evaluates to TRUE.
- If expression is a NULL value, the condition evaluates to FALSE.
Example – With SELECT Statement
Here is an example of how to use the IS NOT NULL condition in a SELECT statement:
SELECT * FROM contacts WHERE last_name IS NOT NULL;
This MySQL IS NOT NULL example will return all records from the contacts table where the last_name does not contain a null value.
Example – With INSERT Statement
Here is an example of how to use the IS NOT NULL condition in an INSERT statement:
INSERT INTO contacts (contact_id, contact_name) SELECT account_no, supplier_name FROM suppliers WHERE category IS NOT NULL;
This MySQL IS NOT NULL example will insert records into the contacts table where the category does not contain a null value.
Example – With UPDATE Statement
Here is an example of how to use the IS NOT NULL condition in an UPDATE statement:
UPDATE contacts SET status = 'completed' WHERE last_name IS NOT NULL;
This MySQL IS NOT NULL example will update records in the contacts table where the last_name does not contain a null value.
Example – With DELETE Statement
Here is an example of how to use the IS NOT NULL condition in a DELETE statement:
DELETE FROM contacts WHERE last_name IS NOT NULL;
This MySQL IS NOT NULL example will delete all records from the contacts table where the last_name does not contain a null value.
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