Function polars::export::arrow::io::parquet::read::get_column_iterator

pub fn get_column_iterator<R>(
    reader: R, 
    metadata: &FileMetaData, 
    row_group: usize, 
    field: usize, 
    page_filter: Option<Arc<dyn Fn(&ColumnDescriptor, &DataPageHeader) + Send + Sync + 'static>>, 
    page_buffer: Vec<u8, Global>
) -> ColumnIterator<R> where
    R: Read + Seek, 

This is supported on crate feature io_parquet only.

Returns a ColumnIterator of column chunks corresponding to field. Contrarily to get_page_iterator that returns a single iterator of pages, this iterator returns multiple iterators, one per physical column of the field. For primitive fields (e.g. i64), ColumnIterator yields exactly one column. For complex fields, it yields multiple columns.