Dewey Dunnington created ARROW-16503: ----------------------------------------
Summary: [C++] Can't concatenate extension arrays Key: ARROW-16503 URL: https://issues.apache.org/jira/browse/ARROW-16503 Project: Apache Arrow Issue Type: Improvement Components: C++ Reporter: Dewey Dunnington It looks like Arrays with an extension type can't be concatenated. From the R bindings: {code:R} library(arrow, warn.conflicts = FALSE) arr <- vctrs_extension_array(1:10) concat_arrays(arr, arr) #> Error: NotImplemented: concatenation of integer(0) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/array/concatenate.cc:195 VisitTypeInline(*out_->type, this) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/array/concatenate.cc:590 ConcatenateImpl(data, pool).Concatenate(&out_data) {code} This shows up more practically when using the query engine: {code:R} library(arrow, warn.conflicts = FALSE) table <- arrow_table( group = rep(c("a", "b"), 5), col1 = 1:10, col2 = vctrs_extension_array(1:10) ) tf <- tempfile() table |> dplyr::group_by(group) |> write_dataset(tf) open_dataset(tf) |> dplyr::arrange(col1) |> dplyr::collect() #> Error in `dplyr::collect()`: #> ! NotImplemented: concatenation of extension<arrow.r.vctrs> #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/array/concatenate.cc:195 VisitTypeInline(*out_->type, this) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/array/concatenate.cc:590 ConcatenateImpl(data, pool).Concatenate(&out_data) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/compute/kernels/vector_selection.cc:2025 Concatenate(values.chunks(), ctx->memory_pool()) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/compute/kernels/vector_selection.cc:2084 TakeCA(*table.column(j), indices, options, ctx) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/compute/exec/sink_node.cc:527 impl_->DoFinish() #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/compute/exec/exec_plan.cc:467 iterator_.Next() #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/record_batch.cc:337 ReadNext(&batch) #> /Users/deweydunnington/Desktop/rscratch/arrow/cpp/src/arrow/record_batch.cc:351 ToRecordBatches() {code} -- This message was sent by Atlassian Jira (v8.20.7#820007)