[HIVE-13452] StatsOptimizer should return no rows on empty table with group by

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0, 1.1.0, 1.2.0, 2.0.0, 2.1.0
• Fix Version/s: 2.3.0
• Component/s: Logical Optimizer
• Assignee: Pengcheng Xiong
• Reporter: Ashutosh Chauhan
• Created: 07/Apr/16 02:08
• Updated: 14/Dec/17 16:25
• Resolved: 13/Dec/16 06:27

Description

create table t1 (a int);
analyze table t1 compute statistics;
analyze table t1 compute statistics for columns;
select count(1) from t1 group by 1;
set hive.compute.query.using.stats=true;
select count(1) from t1 group by 1;

In both cases result set should be empty. However, with statsoptimizer on Hive returns one row with value 0.

Issue Links

• relates to: HIVE-18279 Incorrect condition in StatsOpimizer
• links to: RB