Hi Drill Dev Team!

I am writing a custom storage plugin and I am curious if it is possible
in Drill to pass a filter value, in the form of a where clause, that is
not related to a column. What I would like to accomplish is something like:

select * from myTable where notColumn = 'value';

In the example, notColumn is not a column in myTable, or any other
table, it is just a specific parameter that the storage plugin will use
in the filtering process. Additionally, notColumn would not be returned
as a column so Drill needs to not expect it as a part of the 'select *'.
I created a rule that will push down and remove these non-column filter
calls, but I need to somehow tell drill/calcite that the filter name is
valid, without actually registering it as a column. The following error
occurs prior to submitting any rules:

org.apache.drill.common.exceptions.UserRemoteException: VALIDATION
ERROR: From line 1, column 35 to line 1, column 39: Column 'notColumn'
not found in any table
Alternatively, can I manipulate star queries to only return a subset of
all the columns for a table?

Any insight would be greatly appreciated!

Thanks,
Ryan