Hive版的Pivit和Unpivot实现方式

**

Pivot using Hivemall to_map function.

**

SELECT
  uid,
  kv['c1'] AS c1,
  kv['c2'] AS c2,
  kv['c3'] AS c3
FROM (
  SELECT uid, to_map(key, value) kv
  FROM vtable
  GROUP BY uid
) t

uid c1 c2 c3
101 11 12 13
102 21 22 23

Unpivot