Function csv_extract

src/expr/src/relation/func.rs:3438–3451

(a: Datum<'_>, n_cols: usize)

}

pub fn csv_extract(a: Datum<'_>, n_cols: usize) -> impl Iterator<Item = (Row, Diff)> + '_ {
    let bytes = a.unwrap_str().as_bytes();
    let mut row = Row::default();
    let csv_reader = csv::ReaderBuilder::new()
        .has_headers(false)
        .from_reader(bytes);
    csv_reader.into_records().filter_map(move |res| match res {
        Ok(sr) if sr.len() == n_cols => {
            row.packer().extend(sr.iter().map(Datum::String));
            Some((row.clone(), Diff::ONE))
        }
        _ => None,
    })
}

pub fn repeat_row(a: Datum) -> Option<(Row, Diff)> {
    let n = a.unwrap_int64();