[IMPALA-7588] incorrect HS2 null handling introduced by IMPALA-7477

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: Impala 3.1.0
• Component/s: Backend
• Labels: correctness
• Target Version: Impala 3.1.0
• Epic Color: ghx-label-7
• Assignee: Tim Armstrong
• Reporter: Tim Armstrong
• Created: 18/Sep/18 18:05
• Updated: 19/Sep/18 16:01
• Resolved: 19/Sep/18 16:01

Description

boroknagyz reported this issue with the HS2 endpoint:

Reproduction:

create table null_table (int_field int, float_field float, double_field double, string_field string);
insert into table null_table values (1, 3.14, 3.14, 'abc'), (2, 4.12, 4.12, 'def'), (NULL, NULL, NULL, NULL);

From JDBC client (only tried Hive JDBC client)

select * from null_table;
0 | 0.0 | 0.0 | null
2 | 4.12 | 4.12 | 'def'
0 | 0.0 | 0.0 |

The bug is with handling of nulls in the conversion functions, specifically output_row_idx isn't incremented.

Issue Links

• is broken by: IMPALA-7477 Improve QueryResultSet interface to allow appending a batch of rows at a time