[HIVE-20265] PTF operator has an extra reducer in CBO

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 4.0.0
• Component/s: Query Planning
• Target Version/s: 4.0.0
• Assignee: Vineet Garg
• Reporter: Vineet Garg
• Created: 29/Jul/18 19:59
• Updated: 08/Apr/19 20:13

Description

explain vectorization detail
select p_mfgr, p_name, p_size, 
min(p_retailprice),
rank() over(distribute by p_mfgr sort by p_name)as r,
dense_rank() over(distribute by p_mfgr sort by p_name) as dr,
p_size, p_size - lag(p_size,1,p_size) over(distribute by p_mfgr sort by p_name) as deltaSz
from part
group by p_mfgr, p_name, p_size

Above query generates extra reducer with CBO on.

Issue Links

• relates to: HIVE-19770 Support for CBO for queries with multiple same columns in select