Github user vvysotskyi commented on the issue:
https://github.com/apache/drill/pull/1138
@paul-rogers, schema is taken from the first file in the `FormatSelection`.
Therefore for the case, when we have a table with several files with a
different scheme, Drill query will fail.
As for the plan-time type information, besides the validation at the stage
when a query is converted into rel nodes, field list may be used in project rel
nodes instead of the dynamic star for `DynamicDrillTable`.---
