Samyak2 commented on code in PR #7919: URL: https://github.com/apache/arrow-rs/pull/7919#discussion_r2207280987
########## parquet-variant-compute/src/variant_get.rs: ########## @@ -0,0 +1,202 @@ +// 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 std::sync::Arc; + +use arrow::{ + array::{Array, ArrayRef}, + compute::CastOptions, + error::Result, +}; +use arrow_schema::{ArrowError, Field}; +use parquet_variant::path::VariantPath; + +use crate::{VariantArray, VariantArrayBuilder}; + +/// Returns an array with the specified path extracted from the variant values. +/// +/// The return array type depends on the `as_type` field of the options parameter +/// 1. `as_type: None`: a VariantArray is returned. The values in this new VariantArray will point +/// to the specified path. +/// 2. `as_type: Some(<specific field>)`: an array of the specified type is returned. +pub fn variant_get(input: &ArrayRef, options: GetOptions) -> Result<ArrayRef> { + let variant_array: &VariantArray = input.as_any().downcast_ref().ok_or_else(|| { + ArrowError::InvalidArgumentError( + "expected a VariantArray as the input for variant_get".to_owned(), + ) + })?; + + if let Some(as_type) = options.as_type { + return Err(ArrowError::NotYetImplemented(format!( + "getting a {} from a VariantArray is not implemented yet", + as_type + ))); + } + + let mut builder = VariantArrayBuilder::new(variant_array.len()); + for i in 0..variant_array.len() { + let new_variant = variant_array.value(i); + // TODO: perf? + let new_variant = new_variant.get_path(&options.path); + if let Some(new_variant) = new_variant { + // TODO: we're decoding the value and doing a copy into a variant value again. This + // copy can be much smarter. + builder.append_variant(new_variant); Review Comment: Actually, I tried this out for copying the buffers directly in case of list/object. We're still decoding and encoding in case of top-level primitives though. It's in a separate branch for now. The test is failing because equality on variant is also checking for metadata buffer equality. Here it is: https://github.com/Samyak2/arrow-rs/commit/00bd07dd322fc66791b5decbf0c04a0ddb56f417 If this is what you meant, I'll find a way to make the tests pass and add it here -- 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...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
