Function linear_search

datafusion/common/src/utils/mod.rs:200–215

This function searches for a tuple of given values (`target`) among the given rows (`item_columns`) via a linear scan. It assumes that `item_columns` is sorted according to `sort_options` and returns the insertion index of `target`. Template argument `SIDE` being `true`/`false` means left/right insertion.

(
    item_columns: &[ArrayRef],
    target: &[ScalarValue],
    sort_options: &[SortOptions],
)

/// according to `sort_options` and returns the insertion index of `target`.
/// Template argument `SIDE` being `true`/`false` means left/right insertion.
pub fn linear_search<const SIDE: bool>(
    item_columns: &[ArrayRef],
    target: &[ScalarValue],
    sort_options: &[SortOptions],
) -> Result<usize> {
    let low: usize = 0;
    let high: usize = item_columns
        .first()
        .ok_or_else(|| _internal_datafusion_err!("Column array shouldn't be empty"))?
        .len();
    let compare_fn = |current: &[ScalarValue], target: &[ScalarValue]| {
        let cmp = compare_rows(current, target, sort_options)?;
        Ok(if SIDE { cmp.is_lt() } else { cmp.is_le() })
    };
    search_in_slice(item_columns, target, compare_fn, low, high)
}

/// This function searches for a tuple of given values (`target`) among a slice of
/// the given rows (`item_columns`) via a linear scan. The slice starts at the index