If is null sql w3schools Example: SELECT IFNULL(middle_name, 'N/A') FROM person; *Note: The COALESCE() function works the same as it does for other databases. Click "Run SQL" to execute the SQL statement above. Bonjour, futurs magiciens SQL ! Aujourd'hui, nous allons plonger dans un aspect fascinant de SQL qui a piégé de nombreux étudiants au fil des ans. SQL Statement: SELECT CustomerName, ContactName, Address FROM Customers WHERE Address IS NOT NULL; Edit the SQL Statement, and click "Run SQL" to see the result. EmploymentType is used if it is not NULL. Examples W3Schools offers free online tutorials, references and exercises in all the major languages of the web. See these articles on null. This means that the field will be saved with a NULL value. cn');亲自试一试»定义和用法如果表达式为NULL，则ISNULL()函数返回指定值。 W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Primary keys must contain UNIQUE values, and cannot contain NULL values. macyodxgtpucaygpswndfvwnfftcgatlvuhfxvbedepucgdcszlibqurvxhekpaedthvobeoteks