Function array_element_inner

datafusion/functions-nested/src/extract.rs:192–211

array_element SQL function There are two arguments for array_element, the first one is the array, the second one is the 1-indexed index. `array_element(array, index)` For example: > array_element(\[1, 2, 3], 2) -> 2

(args: &[ArrayRef])

/// For example:
/// > array_element(\[1, 2, 3], 2) -> 2
fn array_element_inner(args: &[ArrayRef]) -> Result<ArrayRef> {
    let [array, indexes] = take_function_args("array_element", args)?;

    match &array.data_type() {
        Null => Ok(Arc::new(NullArray::new(array.len()))),
        List(_) => {
            let array = as_list_array(&array)?;
            let indexes = as_int64_array(&indexes)?;
            general_array_element::<i32>(array, indexes)
        }
        LargeList(_) => {
            let array = as_large_list_array(&array)?;
            let indexes = as_int64_array(&indexes)?;
            general_array_element::<i64>(array, indexes)
        }
        arg_type => {
            exec_err!("array_element does not support type {arg_type}")
        }
    }
}

fn general_array_element<O: OffsetSizeTrait>(
    array: &GenericListArray<O>,