如何在Hive中爆炸地图数组

Question

考虑具有以下结构的表my_table：

>> describe my_table

id               bigint
info_detail      map<bigint,array<string>>

如果爆炸info_detail，我将得到数组：

>> select explode(info_detail) as (info_id, detail) 
   from my_table

   info_id  detail
   112344   ["something about 112344", "other things"]
   342302   ["something about 342302"]

也如何爆炸detail，所以结果看起来像这样：

   info_id  detail
   112344   "something about 112344"
   112344   "other things"
   342302   "something about 342302"

Answer 1

按如下所示分解地图后，应该可以分解数组

select info_id, d from (
select explode(info_detail) as (info_id, detail) 
from my_table
) t lateral view explode(detail) detailexploded as d;

Answer 2

您必须两次explode，一次在map列上，然后在其中的结果array上。

select tbl.info_id,tbl1.details
from my_table m
lateral view explode(info_detail) tbl as info_id,detail 
lateral view explode(detail) tbl1 as details