如何基于Hive中的客户ID索引将行转置为单列？

Question

我有一列带有客户ID的列和一列带有日期标记的列（1至12）。我想将非零日期标志堆积为一列中的日期，并在ID列中重复/替换与它们相对应的ID。

Input Data: 

ID  1       2       3       4       5       6       7       8       9        10     11      12
A   Jan-18  0       0       0       May-18  0       0       0       Sep-18   0      0       0
B   0       0       0       Apr-18  0       0       Aug-18  0       0        0      0       0

Expected Output:

ID  Date
A   Jan-18
A   May-18
A   Sep-18
B   Apr-18
B   Aug-18

Answer 1

使用联合：

select id, col1  as `date`from tablename where col1 > '0'
union   
select id, col2  as `date`from tablename where col2 > '0'
union       
select id, col3  as `date`from tablename where col3 > '0'
union       
select id, col4  as `date`from tablename where col4 > '0'
union       
select id, col5  as `date`from tablename where col5 > '0'
union       
select id, col6  as `date`from tablename where col6 > '0'
union       
select id, col7  as `date`from tablename where col7 > '0'
union        
select id, col8  as `date`from tablename where col8 > '0'
union       
select id, col9  as `date`from tablename where col9 > '0'
union       
select id, col10 as `date`from tablename where col10 > '0'
union      
select id, col11 as `date`from tablename where col11 > '0'
union         
select id, col12 as `date`from tablename where col12 > '0'
;