pub fn compressed_size(&self) -> usize {
        self.columns
            .iter()
            .map(|c| c.compressed_size() as usize)
            .sum::<usize>()
    }
/// Total size of all compressed column data in this row group.
Total size of all compressed column data in this row group.
Total size of all compressed column data in this row group .
pub fn compressed_size(&self) -> usize {
        self.columns
            .iter()
            .map(|c| c.compressed_size() as usize)
            .sum::<usize>()
    }
pub fn compressed_size ( & self ) -> usize { self . columns . iter ( ) . map ( | c | c . compressed_size ( ) as usize ) . sum :: < usize > ( ) }
Total size of all compressed column data in this row group.
Total size of all compressed column data in this row group .
&self