[HIVE-17617] Rollup of an empty resultset should contain the grouping of the empty grouping set

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0
• Component/s: SQL
• Assignee: Zoltan Haindrich
• Reporter: Zoltan Haindrich
• Created: 27/Sep/17 13:49
• Updated: 27/Feb/24 22:24
• Resolved: 25/Oct/17 15:06

Description

running

drop table if exists tx1;
create table tx1 (a integer,b integer,c integer);

select  sum(c),
        grouping(b)
from    tx1
group by rollup (b);

returns 0 rows; however

according to the standard:
The <empty grouping set> is regarded as the shortest such initial sublist. For example, “ROLLUP ( (A, B), (C, D) )”
is equivalent to “GROUPING SETS ( (A, B, C, D), (A, B), () )”.

so I think the totals row (the grouping for () should be present) - psql returns it.

Issue Links

• causes: HIVE-18413 Grouping of an empty result set may only contain null values
• causes: HIVE-18523 Fix summary row in case there are no inputs