Function FIRST_VALUE and LAST_VALUE in fields not working

Summary

When using function="FIRST_VALUE" in a field, the output query inserts the SUM function.

The same behaviour happens when using LAST_VALUE

AWE version

4.1.5

What is the current bug behavior?

With a field like this:

<field id="cie" table="a" function="FIRST_VALUE" alias="value"/>

The output query turns out like this: sum(a.cie) as value

What is the expected correct behavior?

The function should get the first result