tobixdev commented on code in PR #18552: URL: https://github.com/apache/datafusion/pull/18552#discussion_r2675285660
########## datafusion/common/src/types/canonical.rs: ########## @@ -0,0 +1,127 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +use crate::error::_internal_err; +use crate::types::{LogicalType, NativeType, TypeParameter, TypeSignature}; +use crate::Result; +use arrow::array::{Array, FixedSizeBinaryArray}; +use arrow::util::display::{ArrayFormatter, DisplayIndex, FormatOptions, FormatResult}; +use arrow_schema::extension::{ExtensionType, Opaque, Uuid}; +use arrow_schema::DataType; +use std::fmt::Write; +use uuid::Bytes; + +impl LogicalType for Uuid { Review Comment: I see this similar to @paleolimbot . The `LogicalType` / `ExtensionTypeRegistry` pair aims to be the "starting point" where custom type use cases build upon. For example, there is an open issues from myself that [aims to introduce user-defined orderings](https://github.com/apache/datafusion/issues/14828) for the sorting operators. For that purpose we would have a method `LogicalType::ordering_information()` that can be overwritten by extension types and then be used during planning. I think a similar way can create a set of casting operators for extension types. But for a concrete design we would have to look closer at the requirements (e.g., do we want to support `CREATE CAST`). -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
