mysqlselectifnull

MySQL IFNULL ELSE

I have a select statement where I want to make the select conditional like this:

IFNULL(field_a, field_a, field_b)

so that it checks field a. If a is null then the select would be field b.

Is that possible ?

Solution

  • Use COALESCE:

    SELECT COALESCE(field_a, field_b)

    COALESCE is an ANSI standard function that returns the first non-null value from the list of columns specified, processing the columns from left to right. So in the example, if field_a is null, field_b value will be displayed. However, this function will return NULL if there is no non-null value from the columns specified.

    It's supported on MySQL (I've used it on 4.1), SQL Server (since v2000), Oracle 9i+...