[jira] [Commented] (DRILL-4185) UNION ALL involving empty directory on any side of union all results in Failed query

["Khurram Faraaz (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/DRILL-4185?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15051667#comment-15051667 ] 

Khurram Faraaz commented on DRILL-4185:
---------------------------------------

On the other hand if we use an empty file (for example, an empty JSON file named empty.json) in the directory named empty. UNION ALL returns results from the non-empty input.

{code}
[root@centos-01 ~]# hadoop fs -ls /tmp/empty
Found 1 items
-rwxr-xr-x   3 root root          0 2015-11-04 23:43 /tmp/empty/empty.json
{code}

{code}
0: jdbc:drill:schema=dfs.tmp> select key1 from empty UNION ALL select EID from Emp;
+-------+
| key1  |
+-------+
| 100   |
| 10    |
| 2     |
| 50    |
| 55    |
| 67    |
| 113   |
| 119   |
| 89    |
| 57    |
| 61    |
+-------+
11 rows selected (0.42 seconds)
{code}

> UNION ALL involving empty directory on any side of union all results in Failed query
> ------------------------------------------------------------------------------------
>
>                 Key: DRILL-4185
>                 URL: https://issues.apache.org/jira/browse/DRILL-4185
>             Project: Apache Drill
>          Issue Type: Bug
>          Components: Execution - Relational Operators
>    Affects Versions: 1.4.0
>            Reporter: Khurram Faraaz
>
> UNION ALL query that involves an empty directory on either side of UNION ALL operator results in FAILED query. We should return the results for the non-empty side (input) of UNION ALL.
> Note that empty_DIR is an empty directory, the directory exists, but it has no files in it. 
> Drill 1.4 git.commit.id=b9068117
> 4 node cluster on CentOS
> {code}
> 0: jdbc:drill:schema=dfs.tmp> select columns[0] from empty_DIR UNION ALL select cast(columns[0] as int) c1 from `testWindow.csv`;
> Error: VALIDATION ERROR: From line 1, column 24 to line 1, column 32: Table 'empty_DIR' not found
> [Error Id: 5c024786-6703-4107-8a4a-16c96097be08 on centos-01.qa.lab:31010] (state=,code=0)
> 0: jdbc:drill:schema=dfs.tmp> select cast(columns[0] as int) c1 from `testWindow.csv` UNION ALL select columns[0] from empty_DIR;
> Error: VALIDATION ERROR: From line 1, column 90 to line 1, column 98: Table 'empty_DIR' not found
> [Error Id: 58c98bc4-99df-425c-aa07-c8c5faec4748 on centos-01.qa.lab:31010] (state=,code=0)
> {code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)