You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@drill.apache.org by "Sorabh Hamirwasia (JIRA)" <ji...@apache.org> on 2018/11/27 18:24:00 UTC

[jira] [Created] (DRILL-6872) Add support for Join with small build side table between Lateral & Unnest subquery.

Sorabh Hamirwasia created DRILL-6872:
----------------------------------------

             Summary: Add support for Join with small build side table between Lateral & Unnest subquery.
                 Key: DRILL-6872
                 URL: https://issues.apache.org/jira/browse/DRILL-6872
             Project: Apache Drill
          Issue Type: Improvement
          Components: Execution - Flow
            Reporter: Sorabh Hamirwasia


We want to support Hash Join in Lateral & Unnest subquery for special case of small table on build side of the Hash Join. In this case basically build side is a small table which is scanned once by Hash Join and then for each left side batch with EMIT outcome, same build side information is used. The example plan will look like below: 
{code:java}
             LJ
              /    \
        Scan    HashJoin
                     /      \
            Unnest    Scan (Build)
{code}
 
Here we should also think about sniffing logic in Hash Join operator which can cause deadlock for this scenario.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)