Method key

arrow-array/src/array/dictionary_array.rs:405–407

Return the value of `keys` (the dictionary key) at index `i`, cast to `usize`, `None` if the value at `i` is `NULL`.

(&self, i: usize)

    /// Return the value of `keys` (the dictionary key) at index `i`,
    /// cast to `usize`, `None` if the value at `i` is `NULL`.
    pub fn key(&self, i: usize) -> Option<usize> {
        self.keys.is_valid(i).then(|| self.keys.value(i).as_usize())
    }

    /// Returns a zero-copy slice of this array with the indicated offset and length.
    pub fn slice(&self, offset: usize, length: usize) -> Self {