[jira] [Updated] (DRILL-5344) External sort priority queue copier fails with an empty batch

["Zelaine Fong (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/DRILL-5344?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Zelaine Fong updated DRILL-5344:
--------------------------------
    Reviewer: Boaz Ben-Zvi

Assigned Reviewer to [~ben-zvi]

> External sort priority queue copier fails with an empty batch
> -------------------------------------------------------------
>
>                 Key: DRILL-5344
>                 URL: https://issues.apache.org/jira/browse/DRILL-5344
>             Project: Apache Drill
>          Issue Type: Bug
>    Affects Versions: 1.10.0
>            Reporter: Paul Rogers
>            Assignee: Paul Rogers
>            Priority: Minor
>             Fix For: 1.11.0
>
>
> The external sort uses a "priority queue copier" to merge batches when spilling or when merging spilled batches.
> The code will fail with an {{IndexOutOfBoundsException}} if any record batch is empty. The reason is a faulty assumption in generated code:
> {code}
>   public void setup(...) {
>     ...
>       vector4.set(i, i, batchGroups.get(i).getNextIndex());
>     ...
>   }
>   public int getNextIndex() {
>     if (pointer == getRecordCount()) {
>       return -1;
>     }
>     ...
>   }
> {code}
> The code to get the next index returns -1 when the "position" in a record batch is zero. The -1 position translates (when truncated) into 65535 which produces the index exception.
> The workaround has been to special case empty batches elsewhere in the code, apparently to avoid hitting this error.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)