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https://issues.apache.org/jira/browse/FLINK-687?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14561009#comment-14561009
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Chiwan Park commented on FLINK-687:
-----------------------------------
Yes. Splitting this issue into two sub issues is reasonable. :)
I think the outer join algorithm based HashJoin should implemented a class
extending {{HashMatchIteratorBase}} and implementing JoinTaskIterator. Is it
right?
I have another question. There are many match iterators in
{{org.apache.flink.runtime.operators.hash}} package. I know the difference
between {{First}} and {{Second}} but don't know the difference {{Reusing}} and
{{NonReusing}} and the meaning of {{ReOpenable}}. Could you explain me about
this keyword?
If my approach is wrong, please advise me.
Thank you :)
> Add support for outer-joins
> ---------------------------
>
> Key: FLINK-687
> URL: https://issues.apache.org/jira/browse/FLINK-687
> Project: Flink
> Issue Type: New Feature
> Reporter: GitHub Import
> Assignee: Chiwan Park
> Priority: Minor
> Labels: github-import
> Fix For: pre-apache
>
>
> There are three types of outer-joins:
> - left outer,
> - right outer, and
> - full outer
> joins.
> An outer-join does not "filter" tuples of the outer-side that do not find a
> matching tuple on the other side. Instead, it is joined with a NULL value.
> Supporting outer-joins requires some modifications in the join execution
> strategies.
> ---------------- Imported from GitHub ----------------
> Url: https://github.com/stratosphere/stratosphere/issues/687
> Created by: [fhueske|https://github.com/fhueske]
> Labels: enhancement, java api, runtime,
> Created at: Mon Apr 14 12:09:00 CEST 2014
> State: open
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