NULL functions

This section describes functions for returning or detecting NULL values.

All functions can be used in both the data load script and in chart expressions.

Use the drop-down on each function to see a brief description and the syntax of each function. Click the function name in the syntax description for further details.

The EmptyIsNull function converts empty strings to NULL. Hence, it returns NULL if the parameter is an empty string, otherwise it returns the parameter.

EmptyIsNull(expr )

The IsNull function tests if the value of an expression is NULL and if so, returns -1 (True), otherwise 0 (False).

IsNull(expr )

The Null function returns a NULL value.

Null( )