ISNULL function

This function is used to replaces a NULL value with another value.

Function parameters:

The first parameter is an expression of any type

The second parameter is an expression of any type

The first parameter value is returned if this parameter is not NULL; otherwise, the second parameter value is returned.

The second parameter is converted to the type of the first parameter if the type of the first parameter is String or Number.

Example:

// Obtain sum based on Quantity field. If no record
// exists, display 0
SELECT ISNULL(SUM(Quantity), 0) AS Quantity
FROM Document.ExpInvoice.Contents

 

See also: Functions of Query Language