Is Null Nodes in Policy Designer

The following example illustrates how you can use the Is Null node in a policy model to define a default value to be used in subsequent nodes in the scenario where the input value is null.

Consider the following nodes and connections.

As shown in the following image, you can use the Is Null node to check whether or not the Criticality field in the record associated with the AMS Asset node has a value. If there is no value, the Is Null node output will be 0.

Then, as shown in the following image of the Properties window for the Case node, you can now use the output of the Is Null node to map the numeric Criticality values to corresponding character values (HIGH, MEDIUM, and LOW), which are used to populate the Recommendation Priority field when the Create Recommendation node is executed.

Using the Is Null node in this way allows you to translate a null value to an actual value that can be used in subsequent calculations and actions.

The following example illustrates how you can use the Is Null node in a policy model to trigger some action if a particular field is null.

Consider the following nodes and connections.

As shown in the following image, you can use the Is Null node to check whether or not the Criticality field in the record associated with the AMS Asset node has a value. If there is no value, the Is Null node output will be -1. The value -1 was chosen in this case because it is a value that is invalid for criticality; therefore, it serves as an indication that the Criticality field does not contain a value.

The Equal condition node in the policy evaluates whether the value from the Is Null node is equal to -1. If it is, this indicates that the Criticality field contains no value and an email alert is sent.