[DRILL-5165] wrong results - LIMIT ALL and OFFSET clause in same query

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.10.0
• Fix Version/s: 1.11.0
• Component/s: Query Planning & Optimization
• Labels: ready-to-commit
• Assignee: Chunhui Shi
• Reporter: Khurram Faraaz
• Reviewer: Jinfeng Ni
• Created: 27/Dec/16 08:39
• Updated: 08/Aug/17 17:47
• Resolved: 24/Jul/17 10:00

Description

This issue was reported by a user on Drill's user list.
Drill 1.10.0 commit ID : bbcf4b76

I tried a similar query on apache Drill 1.10.0 and Drill returns wrong results when compared to Postgres, for a query that uses LIMIT ALL and OFFSET clause in the same query. We need to file a JIRA to track this issue.

0: jdbc:drill:schema=dfs.tmp> select col_int from typeall_l order by 1 limit all offset 10;
+----------+
| col_int  |
+----------+
+----------+
No rows selected (0.211 seconds)
0: jdbc:drill:schema=dfs.tmp> select col_int from typeall_l order by col_int limit all offset 10;
+----------+
| col_int  |
+----------+
+----------+
No rows selected (0.24 seconds)

Query => select col_int from typeall_l limit all offset 10;
Drill 1.10.0 returns 85 rows

whereas for same query,
postgres=# select col_int from typeall_l limit all offset 10;
Postgres 9.3 returns 95 rows, which is the correct expected result.

Query plan for above query that returns wrong results

0: jdbc:drill:schema=dfs.tmp> explain plan for select col_int from typeall_l limit all offset 10;
+------+------+
| text | json |
+------+------+
| 00-00    Screen
00-01      Project(col_int=[$0])
00-02        SelectionVectorRemover
00-03          Limit(offset=[10])
00-04            Scan(groupscan=[ParquetGroupScan [entries=[ReadEntryWithPath [path=maprfs:///tmp/typeall_l]], selectionRoot=maprfs:/tmp/typeall_l, numFiles=1, usedMetadataFile=false, columns=[`col_int`]]])

Issue Links

• links to: GitHub Pull Request #776