Function count_rows_from_slice_par

pub fn count_rows_from_slice_par(
    bytes: &[u8],
    separator: u8,
    quote_char: Option<u8>,
    comment_prefix: Option<&CommentPrefix>,
    eol_char: u8,
    has_header: bool,
    skip_lines: usize,
    skip_rows_before_header: usize,
    skip_rows_after_header: usize,
) -> Result<usize, PolarsError>

Read the number of rows without parsing columns useful for count(*) queries