Github user MikeThomsen commented on the issue:
https://github.com/apache/nifi/pull/2777
@ijokarumawak
> Adding those values into lookup coordinate may not sound that wrong, if
we keep the consistent overlaying order.
It is, however, dangerous to do with LookupService implementations that are
based around query builders like the Mongo one. The Mongo one does a straight
conversion of the coordinate map into a Mongo query, so if you add any value
other than a key the user specifies you will break the query in most cases.
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