[PHOENIX-1362] Min/max aggregate query on CHAR and BINARY types always return null

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.1.0
• Fix Version/s: 4.3.0, 3.3.0, 4.2.3, 3.2.3
• Labels: aggregate char

Environment

HBase 0.98.4
RHEL 6.5

• Assignee: Dave Hacker
• Reporter: Hari Krishna Dara
• Created: 17/Oct/14 06:56
• Updated: 01/Aug/23 08:04
• Resolved: 17/Dec/14 00:28

Description

• Create a table with CHAR type and insert a few strings that start with 0.
• Select min()/max() on the column, you always get null value.

0: jdbc:phoenix:isthbase01-mnds2-1-crd> create table TT(VAL1 integer not null, VAL2 char(2), val3 varchar, VAL4 varchar constraint PK primary key (VAL1));
0: jdbc:phoenix:isthbase01-mnds2-1-crd> upsert into TT values (0, '00', '00', '0');
0: jdbc:phoenix:isthbase01-mnds2-1-crd> upsert into TT values (1, '01', '01', '1');
0: jdbc:phoenix:isthbase01-mnds2-1-crd> upsert into TT values (2, '02', '02', '2');
0: jdbc:phoenix:isthbase01-mnds2-1-crd> select * from TT;
+------------+------+------------+------------+
|    VAL1    | VAL2 |    VAL3    |    VAL4    |
+------------+------+------------+------------+
| 0          | 00   | 00         | 0          |
| 1          | 01   | 01         | 1          |
| 2          | 02   | 02         | 2          |
+------------+------+------------+------------+
0: jdbc:phoenix:isthbase01-mnds2-1-crd> select min(VAL1), max(VAL1) from TT;
+------------+------------+
| MIN(VAL1)  | MAX(VAL1)  |
+------------+------------+
| 0          | 2          |
+------------+------------+
0: jdbc:phoenix:isthbase01-mnds2-1-crd> select min(VAL2), max(VAL2) from TT;
+------------+------------+
| MIN(VAL2)  | MAX(VAL2)  |
+------------+------------+
| null       | null       |
+------------+------------+
0: jdbc:phoenix:isthbase01-mnds2-1-crd> select min(VAL3), max(VAL3) from TT;
+------------+------------+
| MIN(VAL3)  | MAX(VAL3)  |
+------------+------------+
| 00         | 02         |
+------------+------------+
0: jdbc:phoenix:isthbase01-mnds2-1-crd> select min(VAL4), max(VAL4) from TT;
+------------+------------+
| MIN(VAL4)  | MAX(VAL4)  |
+------------+------------+
| 0          | 2          |
+------------+------------+

As you can see, the query on VAL2 which is of type CHAR(2) returns null, while the same exact values on VAL3 which is of type VARCHAR work as expected.

Issue Links

• links to: GitHub Pull Request #31