Oracle SOA Suite 12c- IgnoreMissingFromData

This post is focused on the magical attribute of oracle BPEL process manager i.e. IgnoreMissingFromData. Let me explain the business scenario-

I have created a SOA service using a BPEL process and I am using an invoke activity inside BPEL process. However, I have a scenario where I have to map input schema (xsd) elements to external web service payload variable using assign activity but the problem is that sometimes my input schema elements are empty i.e. if input schema element contains 5 variables then sometimes 3 or 2 or 1 element is empty. 

This is causing runtime error in BPEL "Selection Failure". To solve this error, either I do transformation using XSL or if-else/switch in my BPEL process. Basically I would like to pass only available elements in input payload. So there is a magical attribute IgnoreMissingFromData  that comes with assign activity. Once the variables assignment has been done, below steps can be used to apply this-

What this does actually?

This attribute simply ignores the input variable in case of empty node or empty value and runtime error Selection Failure doesn't comes.