December 2010
1 post
3 tags
NullPointerException when performing a join with...
If you get this NullPointer exception when joining two tables in hadoop hive, the problem may be that in one of the two tables the join key value is “” (blank string).
For example, if you’re running this query:
select users.id, locations.address from users left outer join locations on users.location_id = locations.id;
and users.location_id happens to be “”...