[IMPALA-502] Impala does not return NULL for case where table has extra string column and data does not (it returns an empty string)

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 1.1
• Fix Version/s: Impala 1.1.1
• Assignee: Skye Wanderman-Milne
• Reporter: Lenni Kuff
• Created: 31/Jul/13 19:05
• Updated: 03/Aug/13 00:37
• Resolved: 03/Aug/13 00:37

Description

Impala does not return NULL for case where table has extra string column and data does not (it returns an empty string).

Repro:

use functional;
create external table jointbl_test like jointbl;
alter table jointbl_test set location '/test-warehouse/jointbl';
select * from jointbl_test;
alter table jointbl_test add columns(s string);
+---------+-----------+----------+-------------+---+
| test_id | test_name | test_zip | alltypes_id | s |
+---------+-----------+----------+-------------+---+
| 1001    | Name1     | 94611    | 5000        |   |
| 1002    | Name2     | 94611    | 5000        |   |
| 1003    | Name3     | 94611    | 5000        |   |
+---------+-----------+----------+-------------+---+

-- Change to an INT col, result is NULL
alter table jointbl_test replace columns(s i int);

+---------+-----------+----------+-------------+------+
| test_id | test_name | test_zip | alltypes_id | i    |
+---------+-----------+----------+-------------+------+
| 1001    | Name1     | 94611    | 5000        | NULL |
| 1002    | Name2     | 94611    | 5000        | NULL |
| 1003    | Name3     | 94611    | 5000        | NULL |
+---------+-----------+----------+-------------+------+