Hive行转列过程中使用LATERAL VIEW遇到空MAP或者空数组的情况

背景：

HIve在进行行转列的过程中，如果遇到转的数组或者MAP()的情况，会出现一种特殊情况，就是数据会消失：

原数据： 

   SELECT

            '1' AS id,

            MAP() AS purchase_info

        UNION ALL

        SELECT

            '2' AS id,

            MAP() AS purchase_info

        UNION ALL

        SELECT

            '3' AS id,

            str_to_map('2019-11-28:100,2019-11-27:1') AS purchase_info

        UNION ALL

        SELECT

            '3' AS id,

            str_to_map('2019-11-28:200,2019-11-27:2') AS purchase_info

    ) all LATERAL VIEW OUTER EXPLODE(purchase_in