currently there is no way to override the default behavior

--schema-from-parquet

we would like to be able to specify the columns and data types.
Maybe it is possible that Parquet exported from CH has this information (or it can be added) but to import Parquet in general, we need to be able to specify columns (including calculated ones, or default values).

We can just start with the data types (or data type mapping).

A CH Date would translate into UInt16 and would become an Integer in Iceberg ... by default.
A CH DateTime would also translate to Integer.