Parquet: How to do concurrent decoding over columns?

[Liyixin95]

Which part is this question about

parquet's api.

Describe your question

How to do concurrent read/decoding over columns? The similar code can be found in polars

I found the build_array_reader function, but I can't construct a ParquetField, which is the input param of this function.

Additional context

[tustvold]

We currently only support parallelizing reads at the row group level. In practice this is usually plenty, although if you wanted to add support for this I'd be happy to provide some pointers

[Liyixin95]

although if you wanted to as support for this I'd be happy to provide some pointers

Yes please, I would like to have a try.

[tustvold]

Ok I'll have a think about how to approach this and get back to you in a couple of days

[Liyixin95]

Ok I'll have a think about how to approach this and get back to you in a couple of days

hello, have you found any approach?