[HIVE-21413] Bad result using UNION with same table

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: 1.2.1
• Component/s: hpl/sql

Environment

engine = mr

TBLPROPERTIES(
    'auto.purge'='true',
    'orc.compress'='ZLIB',
    'serialization.null.format'=''
)

 

• Assignee: Unassigned
• Reporter: Stéphane
• Created: 08/Mar/19 14:14
• Updated: 13/Mar/19 12:10
• Resolved: 11/Mar/19 11:22

Description

Hi,

I have a table named "sau' with 1000 rows.

The table structure is :
 

col_name	data_type	comment
id	string
mnta	int
mntb	int

select id, 'A' as info, mntA as mnt from sau
union
select id, 'B' as info, mntB as mnt from sau

==> return only rows with "info=B"

with
cte_union as (
select id, 'A' as info, mntA as mnt from sau
union
select id, 'B' as info, mntB as mnt from sau
)
select
count
from
cte_union

==> return 1000 but should be 2000
 
I don't know if this bug is fixed on new version.

Using "union all" clause, the result is correct.

Issue Links

• is part of: HIVE-15680 Incorrect results when hive.optimize.index.filter=true and same ORC table is referenced twice in query