alamb commented on issue #12788:
URL: https://github.com/apache/datafusion/issues/12788#issuecomment-2402419364

   > Yes, we need to support binary -> utf8view in arrow cast
   
   Casting from binary --> utf8view via `cast` will work, but won't be much/any 
faster than it is done today
   
   BTW thinking more about this, I do think we need to support the cast, but in 
this PR we should effectively change the *file* schema (not just the table 
schema) when we setup the parquet reader (specifically with 
[`ArrowReaderOptions::with_schema`](https://docs.rs/parquet/latest/parquet/arrow/arrow_reader/struct.ArrowReaderOptions.html#method.with_schema))
   
   Here is the code that does so for `Utf8` --> `Utf8View`
   
   
   
https://github.com/apache/datafusion/blob/b821929194c0ae3d3d5e862e0f82a0e5dc55702f/datafusion/core/src/datasource/physical_plan/parquet/opener.rs#L126-L129
   
   I think we need to also allow the switch when the table schema is `Utf8View` 
and the file schema  is Binary/BinaryView


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