Hi Ravi,
the DT static analysis is not able to perform analysis on tables which use the extended DT expressions such as those using the ? magic dmn variable.
So the analysis for the table results in Skipped at the first DT extended expression, and a Warn is emitted.
Just FYI, the idiomatic way to represent "not null" in a DMN decision table actuially is
not(null)
The !=null alone is not a valid unary test, while
? != null
would be a valid extended DT expression, but for the purpose of DT I would strongly recommend sticking to valid unary tests such as
not(null)
Hope this clarifies,
MM