java通过使用配置单元查询可以将表数据转换为复杂类型列表<structure>？

Question

这是表格的详细信息

Id    Data  
a     {"col1":"11.0","col2":30.0}  
a     {"col1":"12.0","col2":10.0}  
b     {"col1":"11.0","col2":20.0}  
b     {"col1":"12.0","col2":25.0}  
b     {"col1":"15.0","col2":25.0}  
c     {"col1":"12.0","col2":15.0}  
c     {"col1":"13.0","col2":16.0}  

预期输出-按Id分组的数据结构列表

ID  Data  
a   list[ {"col1":"11.0","col2":30.0},{"col1":"12.0","col2":10.0}]  
b   list[ {"col1":"11.0","col2":20.0},{"col1":"12.0","col2":25.0},{"col1":"15.0","col2":25.0}]  
c   list[ {"col1":"12.0","col2":15.0},{"col1":"13.0","col2":16.0}] 

是否可能由配置单元支持的函数实现，或者是否需要编写任何用户定义的函数

Answer 1

简而言之，答案是肯定的，之前也有关于这个问题的答案，请参见此处

How to get array/bag of elements from Hive group by operator?

但总而言之，如果您只有唯一的元素，则使用collect\u set，否则使用collect\u list（仅适用于配置单元0.13+），此外，它是一个标准的分组查询