davisusanibar opened a new issue, #35579:
URL: https://github.com/apache/arrow/issues/35579
### Describe the enhancement requested
Current `field_ref` Expression are able to support ref by Column Name but
does not offer support for Column Index.
Will be useful to also support Column index in case some integration need to
pass Column index instead of Column name.
Reproduce message error:
```c++
void reproduceInferringColumnProjection(){
const std::string& directory_base =
"/Users/dsusanibar/voltron/fork/consumer-testing/tests/data/tpch_parquet/poc/";;
// const std::string& directory_base =
"/diretory_of_your_parquet_file/nation_tpch/";;
std::shared_ptr<arrow::fs::LocalFileSystem> fs =
std::make_shared<arrow::fs::LocalFileSystem>();
arrow::fs::FileSelector selector;
selector.base_dir = directory_base;
selector.recursive = true;
std::vector<arrow::fs::FileInfo> file_infos =
fs->GetFileInfo(selector).ValueOrDie();
int num_printed = 0;
auto format =
std::make_shared<arrow::dataset::ParquetFileFormat>();
arrow::dataset::FileSystemFactoryOptions options;
std::shared_ptr<arrow::dataset::DatasetFactory> dataset_factory =
(arrow::dataset::FileSystemDatasetFactory::Make(fs, selector,
format, options)).ValueOrDie();
std::shared_ptr<arrow::dataset::Dataset> dataset =
(dataset_factory->Finish()).ValueOrDie();
arrow::dataset::ScannerBuilder scanner_builder(dataset);
// Error: NotImplemented: Inferring column projection from FieldRef
FieldRef.FieldPath(0)
scanner_builder.Project({compute::call("add", {compute::field_ref(0),
compute::literal(10)})}, {"column_0"});
// OK there are support in case we use Column Name instead of Column
Index
// scanner_builder.Project({compute::call("add",
{compute::field_ref("n_nationkey"), compute::literal(10)})}, {"column_0"});
std::shared_ptr<arrow::dataset::Scanner> scanner =
scanner_builder.Finish().ValueOrDie();
std::shared_ptr<arrow::Table> table = scanner->ToTable().ValueOrDie();
std::cout << "Table with " << table->num_rows() << " rows and " <<
table->num_columns() << " columns" << std::endl;
std::cout << table->ToString() << std::endl;
}
```
Message error:
```
NotImplemented: Inferring column projection from FieldRef
FieldRef.FieldPath(0)
```
### Component(s)
C++
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