vaibhawvipul commented on code in PR #627: URL: https://github.com/apache/datafusion-comet/pull/627#discussion_r1676111480
########## native/core/src/execution/datafusion/expressions/cast.rs: ########## @@ -500,19 +500,27 @@ impl Cast { let to_type = &self.data_type; let array = array_with_timezone(array, self.timezone.clone(), Some(to_type))?; let from_type = array.data_type().clone(); - - // unpack dictionary string arrays first - // TODO: we are unpacking a dictionary-encoded array and then performing - // the cast. We could potentially improve performance here by casting the - // dictionary values directly without unpacking the array first, although this - // would add more complexity to the code let array = match &from_type { DataType::Dictionary(key_type, value_type) if key_type.as_ref() == &DataType::Int32 && (value_type.as_ref() == &DataType::Utf8 || value_type.as_ref() == &DataType::LargeUtf8) => { - cast_with_options(&array, value_type.as_ref(), &CAST_OPTIONS)? + let dict_array = array + .as_any() + .downcast_ref::<DictionaryArray<Int32Type>>() + .expect("Expected a dictionary array"); + + let casted_dictionary = DictionaryArray::<Int32Type>::new( + dict_array.keys().clone(), + self.cast_array(dict_array.values().clone())?, + ); + + let casted_result = match to_type { + DataType::Dictionary(_, _) => Arc::new(casted_dictionary.clone()), Review Comment: awaiting @viirya 's comment before making any change. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org