[IMPALA-2527] Simple nested query takes an extremely long time

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: Impala 2.3.0
• Fix Version/s: Impala 2.3.0
• Environment: Machine: c2118.hal.cloudera.com 81b1dc54e067b771b587eb3c9be96d70d9df8a7d
• Target Version: Impala 2.3.0
• Assignee: Martin Grund
• Reporter: Taras Bobrovytsky
• Created: 10/Oct/15 00:27
• Updated: 13/Jan/16 22:30
• Resolved: 14/Oct/15 21:01

Description

Query:

use random_data;
select key from table_3.field_33.field_35.value.value limit 5

I cancelled the query after 1 hour. It seemed to be not making any progress, but impalad memory usage was steadily rising.

Impala webpage displayed this for the entire hour:

State: FINISHED
Scan Progress: 0 / 9576 ( 0%)

When the query is changed to:

use random_data;
select count(*) from table_3.field_33.field_35.value.value

it incorrectly returns 0.