Is your feature request related to a problem or challenge? Please describe what you are trying to do.
Today, DataFusion's expression evaluation does not work natively on DictionaryArrays; Instead what happens is that the DictionaryArrays are unpacked into their base type (e.g. a string dictionary gets unpacked into a StringArray)

This is very inefficient, especially for expressions like col != 'foo' -- if col is a DictionaryArray this filter could be applied by finding 'foo' in the dictionary and then checking for values with that dictionary index, and the dictionary could be reused at the output.

Describe the solution you'd like
When

That probably looks something like:

• implement the arrow compute kernels Add native comparison kernel support for DictionaryArray arrow-rs#869
• change coercion rules for binary expressions to avoid casting (unpacking) dictionaries into the base arrays
• Call appropriate arrow compute kernels in binary.rs

Describe alternatives you've considered

Additional context
See #87 for more detail

There are several other operation where dictionary calculation could be much better (e.g. hash aggregate, join, etc)