技術標籤：Hivehive行轉列列轉行

hive錶行轉列和列轉行

行轉列（lateral view explode）

--使用側檢視lateral view explode進行行轉列
create table t3 as with r1 as (select item ,nums from t1  lateral view explode(split(num,",")) t as nums) select * from r1;

select * from t3;

+----------+----------+--+
 

| t3.item  | t3.nums  |
+----------+----------+--+
| A        | 1        |
| A        | 2        |
| A        | 3        |
| A        | 4        |
| B        | 2        |
| B        | 5        |
| B        | 1        |
+----------+----------+--+

t3

列轉行（collect_list,concat_ws）

--使用collect_list和concat_ws進行列轉行
select item ,concat_ws(",",collect_list(nums)) as num from t3 group by item;

+-------+----------+--+
| item  |   num    |
+-------+----------+--+
| A     | 1,2,3,4  |
| B     | 2,5,1    |
+-------+----------+--+