[jira] [Commented] (DRILL-1750) Querying directories with JSON files returns incomplete results

["Steven Phillips (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/DRILL-1750?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14615840#comment-14615840 ] 

Steven Phillips commented on DRILL-1750:
----------------------------------------

There are actually 2 issues here. One of them is the fact that sqlline will not display any columns that are not included in the first batch it receives. This is covered by DRILL-2134.

There is also a bug that causes index out of bounds when there is a changing schema. I don't know if this is the same error reported in this jira. It happens when a file does not contain a column that did exist in a previous file. The ScanBatch still outputs the vector corresponding to this missing field, but in this case, the vector's value count is not set, which results in the buffer not being serialized correctly. This may have also been the cause of the JVM crashes.

> Querying directories with JSON files returns incomplete results
> ---------------------------------------------------------------
>
>                 Key: DRILL-1750
>                 URL: https://issues.apache.org/jira/browse/DRILL-1750
>             Project: Apache Drill
>          Issue Type: Bug
>          Components: Storage - JSON
>            Reporter: Abhishek Girish
>            Assignee: Steven Phillips
>            Priority: Critical
>             Fix For: 1.2.0
>
>         Attachments: 1.json, 2.json, 3.json, 4.json
>
>
> I happened to observe that querying (select *) a directory with json files displays only fields common to all json files. All corresponding fields are displayed while querying each of the json files individually. And in some scenarios, querying the directory crashes sqlline.
> The example below may help make the issue clear:
> > select * from dfs.`/data/json/tmp/1.json`;
> +------------+------------+------------+
> |   artist   |  track_id  |   title    |
> +------------+------------+------------+
> | Jonathan King | TRAAAEA128F935A30D | I'll Slap Your Face (Entertainment USA Theme) |
> +------------+------------+------------+
> 1 row selected (1.305 seconds)
> > select * from dfs.`/data/json/tmp/2.json`;
> +------------+------------+------------+------------+
> |   artist   | timestamp  |  track_id  |   title    |
> +------------+------------+------------+------------+
> | Supersuckers | 2011-08-01 20:30:17.991134 | TRAAAQN128F9353BA0 | Double Wide |
> +------------+------------+------------+------------+
> 1 row selected (0.105 seconds)
> > select * from dfs.`/data/json/tmp/3.json`;
> +------------+------------+------------+
> | timestamp  |  track_id  |   title    |
> +------------+------------+------------+
> | 2011-08-01 20:30:17.991134 | TRAAAQN128F9353BA0 | Double Wide |
> +------------+------------+------------+
> 1 row selected (0.083 seconds)
> > select * from dfs.`/data/json/tmp/4.json`;
> +------------+------------+
> |  track_id  |   title    |
> +------------+------------+
> | TRAAAQN128F9353BA0 | Double Wide |
> +------------+------------+
> 1 row selected (0.076 seconds)
> > select * from dfs.`/data/json/tmp`;
> +------------+------------+
> |  track_id  |   title    |
> +------------+------------+
> | TRAAAQN128F9353BA0 | Double Wide |
> | TRAAAQN128F9353BA0 | Double Wide |
> | TRAAAEA128F935A30D | I'll Slap Your Face (Entertainment USA Theme) |
> | TRAAAQN128F9353BA0 | Double Wide |
> +------------+------------+
> 4 rows selected (0.121 seconds)
> JVM Crash occurs at times:
> > select * from dfs.`/data/json/tmp`;
> +------------+------------+------------+
> | timestamp  |  track_id  |   title    |
> +------------+------------+------------+
> | 2011-08-01 20:30:17.991134 | TRAAAQN128F9353BA0 | Double Wide |
> #
> # A fatal error has been detected by the Java Runtime Environment:
> #
> #  SIGSEGV (0xb) at pc=0x00007f3cb99be053, pid=13943, tid=139898808436480
> #
> # JRE version: OpenJDK Runtime Environment (7.0_65-b17) (build 1.7.0_65-mockbuild_2014_07_16_06_06-b00)
> # Java VM: OpenJDK 64-Bit Server VM (24.65-b04 mixed mode linux-amd64 compressed oops)
> # Problematic frame:
> # V  [libjvm.so+0x932053]
> #
> # Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
> #
> # An error report file with more information is saved as:
> # /tmp/jvm-13943/hs_error.log
> #
> # If you would like to submit a bug report, please include
> # instructions on how to reproduce the bug and visit:
> #   http://icedtea.classpath.org/bugzilla
> #
> Aborted



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