Function parquet2::read::get_column_iterator
source · pub fn get_column_iterator<R: Read + Seek>(
reader: R,
row_group: &RowGroupMetaData,
field_name: &str,
page_filter: Option<PageFilter>,
scratch: Vec<u8>,
max_page_size: usize
) -> ColumnIterator<R>
Expand description
Returns a ColumnIterator
of column chunks corresponding to field
.
Contrarily to get_page_iterator
that returns a single iterator of pages, this iterator
iterates over columns, one by one, and returns a PageReader
per column.
For primitive fields (e.g. i64
), ColumnIterator
yields exactly one column.
For complex fields, it yields multiple columns.
max_page_size
is the maximum number of bytes allowed.