Github user fhueske commented on the issue:
https://github.com/apache/flink/pull/6252
Thanks for opening this PR @HeartSaVioR! (cc @twalthr)
I thought about this again and I don't think we should make the method
public. The problem is that `Expression` is one of the core classes of the
Table API. By making the method public it becomes visible to all users of the
API.
A better approach is to provide a publicly accessible util object (in
org.apache.flink.table.api...) that provides access to the result type (and
possibly other properties) of ab `Expression`.
What do you think?
Best, Fabian
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