SQL Functions

$IFNULL

$IFNULL specifies a return value for columns that contain null values. The column datatype and the return value datatype must match.

If column-value is NULL then return specified-value, else return column-value

Note that use of this function could change the results of a calculated average. A true NULL is generally not included in a count and thus not included in an average. A NULL altered with this function will be included in the count and the average.

Syntax

$IFNULL(column, specified-value)

$IFNULL()

Required.

column

Required. Column name that might contain a null value.

specified-value

Required. The value to return if the column value is null. This value must be of the same datatype as the column.

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Example

select company,

$IFNULL(contact, "No contact")

from customers
where company='systems'

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