[DRILL-6524] Two CASE statements in projection influence results of each other

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.11.0
• Fix Version/s: 1.16.0
• Component/s: Query Planning & Optimization
• Labels: ready-to-commit

Environment

Linux 3.10.0-693.21.1.el7.x86_64 #1 SMP Wed Mar 7 19:03:37 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux,

NAME="CentOS Linux"
VERSION="7 (Core)"

apache drill 1.11.0, 

openjdk version "1.8.0_171"
OpenJDK Runtime Environment (build 1.8.0_171-b10)
OpenJDK 64-Bit Server VM (build 25.171-b10, mixed mode)

• Assignee: Vova Vysotskyi
• Reporter: Oleksandr Chornyi
• Reviewer: Vitalii Diravka
• Created: 21/Jun/18 13:48
• Updated: 15/Mar/19 07:08
• Resolved: 15/Mar/19 04:30

Description

Steps to Reproduce

Run the following query via sqlline:

select
  case when expr$0 = 3 then expr$0 else expr$1 end,
  case when expr$0 = 1 then expr$0 else expr$1 end
from (values(1, 2));

Actual Results

+---------+---------+
| EXPR$0  | EXPR$1  |
+---------+---------+
| 2       | 2       |
+---------+---------+

Expected Results

+---------+---------+
| EXPR$0  | EXPR$1  |
+---------+---------+
| 2       | 1       |
+---------+---------+

Note, that changing order of CASE statements fixes the issue. The following query yields correct results:

select
  case when expr$0 = 1 then expr$0 else expr$1 end,
  case when expr$0 = 3 then expr$0 else expr$1 end
from (values(1, 2));

Issue Links

• is related to: DRILL-5683 Incorrect query result when query uses NOT(IS NOT NULL) expression
• relates to: DRILL-5581 Query with CASE statement returns wrong results
• relates to: DRILL-6722 Query from parquet with case-then and arithmetic operation returns a wrong result
• links to: GitHub Pull Request #1686