Forum Discussion

SGArchitect's avatar
SGArchitect
New Contributor II
4 years ago

Parameters are not being recognized in output stream of UNION snap

I am using UNION snap to get input streams from 2 snaps. Next to the UNION snap, I have a MAPPER snap that tries to access the output stream of UNION snap. Please see attached screenshot. I can s...
SpiroTaleski's avatar
SpiroTaleski
Valued Contributor
4 years ago

@SGArchitect

That is happening because the output of the Union Snap will produce multiple documents(from both inputs). And some of the documents does not contains the value that you are referring to, which throws an error.

By checking the “null safe acess” in the mapper snap will prevent the error, and on the output of the mapper snap you will have the same number of documents as input. The documents that does not contains the path that you are referring will have “null” value on output.

BR,
Spiro Taleski