mysql isnull

The ISNULL() function in MySQL is used to check if an expression is NULL or not. It returns 1 if the expression is NULL, otherwise, it returns 0.

The syntax of the ISNULL() function in MySQL is as follows:

ISNULL(expression)

Here, the expression is the value or column that you want to check for NULL.

For example, to check if the value of the "email" column in a table is NULL or not, you can use the following query:

SELECT * FROM users WHERE ISNULL(email);

This query will return all the rows from the "users" table where the value of the "email" column is NULL.