ifnull in mysql code example

Example 1: mysql ifnull

##syntax:
SELECT IFNULL(col_with_null_value, default_value);

##you can see the result select with the string NA where the document is null:
SELECT IFNULL(user_document_id, 'NA');

Example 2: if column value is null then in mysql

SELECT 
    contactname, IFNULL(bizphone, homephone) phone
FROM
    contacts;

Example 3: mysql select default if null

IFNULL(MAX(EMAIL), "[email protected]") as email