[SPARK-29701] Different answers when empty input given in GROUPING SETS

• Type: Sub-task
• Status: Closed
• Priority: Critical
• Resolution: Won't Fix
• Affects Version/s: 2.4.0, 2.4.1, 2.4.2, 2.4.3, 2.4.4, 3.0.0
• Component/s: SQL
• Labels: correctness
• Assignee: Unassigned
• Reporter: Takeshi Yamamuro
• Created: 01/Nov/19 04:36
• Updated: 12/Dec/22 18:10
• Resolved: 01/May/20 06:27

Description

A query below with an empty input seems to have different answers between PgSQL and Spark;

postgres=# create table gstest_empty (a integer, b integer, v integer);
CREATE TABLE
postgres=# select a, b, sum(v), count(*) from gstest_empty group by grouping sets ((a,b),());
 a | b | sum | count 
---+---+-----+-------
   |   |     |     0
(1 row)

scala> sql("""select a, b, sum(v), count(*) from gstest_empty group by grouping sets ((a,b),())""").show
+---+---+------+--------+
|  a|  b|sum(v)|count(1)|
+---+---+------+--------+
+---+---+------+--------+
 

Issue Links

• is related to: SPARK-29708 Different answers in aggregates of duplicate grouping sets
• links to: GitHub Pull Request #27233
• links to: GitHub Pull Request #27305