pub fn count_rows_from_reader_par(
reader: ByteSourceReader<ReaderSource>,
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,
raise_if_empty: bool,
decompressed_size_hint: Option<usize>,
) -> Result<usize, PolarsError>Available on crate feature
polars-io only.Expand description
Read the number of rows without parsing columns. Useful for count(*) queries. Supports transparent decompression. Does not support truncated compressed files.