您可以使用window函数为要添加的每一行生成一个临时索引。

select 
   k, v , unix_timestamp(ts) as ts, 
   row_number() over ( partition by k,v ) as rn  
from ts_test

这将产生：

+----+----+----------+---+
|   k|   v|        ts| rn|
+----+----+----------+---+
|key1|val1|1486101600|  1|
|key1|val1|1486101600|  2|
|key1|val2|1486101600|  1|
|key1|val2|1486101600|  2|
|key2|val1|1486101600|  1|
+----+----+----------+---+

现在您可以继续并将其添加到您的时间字符串中，因为它已经是iso格式的了。

SELECT a.k, a.v, from_unixtime(ts+rn) as newts from 
   ( select k, v , unix_timestamp(ts) as ts, row_number() over ( partition by k,v ) as rn  
from ts_test )a 

+----+----+-------------------+
|   k|   v|              newts|
+----+----+-------------------+
|key1|val1|2017-02-03 00:00:01|
|key1|val1|2017-02-03 00:00:02|
|key1|val2|2017-02-03 00:00:01|
|key1|val2|2017-02-03 00:00:02|
|key2|val1|2017-02-03 00:00:01|
+----+----+-------------------+

如@dudumarkovitz所述，这也可以通过单一选择实现：

select 
   k, v , 
   from_unixtime(unix_timestamp(ts) + row_number() over ( partition by k,v order by v asc ) ) 
from ts_test