isNull

isNull evaluates an expression to see if it is null. If the expression is null, isNull returns true, and otherwise it returns false.

Syntax

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isNull(expression)

Arguments

expression

The expression to be evaluated as null or not. It can be a field name like address1 or a call to another function that outputs a string.

Return type

Boolean

Example

The following example evaluates the sales_amount field for null values.

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isNull(salesAmount)

The following are the given field values.

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20.13
(null)
57.54

For these field values, the following values are returned.

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false
true
false

The following example tests for a NULL value in an ifelse statement and returns a human-readable value instead.

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ifelse( isNull({ActiveFlag}) , 'Inactive',  'Active')