flink-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF GitHub Bot (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (FLINK-7798) Add support for windowed joins to Table API
Date Sat, 14 Oct 2017 07:51:00 GMT

    [ https://issues.apache.org/jira/browse/FLINK-7798?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16204526#comment-16204526

ASF GitHub Bot commented on FLINK-7798:

Github user xccui commented on a diff in the pull request:

    --- Diff: docs/dev/table/tableApi.md ---
    @@ -498,6 +499,23 @@ Table left = tableEnv.fromDataSet(ds1, "a, b, c");
     Table right = tableEnv.fromDataSet(ds2, "d, e, f");
     Table result = left.join(right).where("a = d").select("a, b, e");
     {% endhighlight %}
    +        <p><b>Note:</b> Currently, only time-windowed inner joins can
be processed in a streaming fashion.</p>
    +        <p>A time-windowed join requires a special join condition that bounds the
time on both sides. This can be done by two appropriate range predicates (<code> &lt;,
&lt;=, &gt;=, &gt;</code>) that compares the <a href="streaming.html#time-attributes">time
attributes</a> of both input tables. The following rules apply for time predicates:
    +          <ul>
    +            <li>Time predicates must compare time attributes of both input tables.</li>
    +            <li>Time predicates must compare only time attributes of the same type,
i.e., processing time with processing time or event time with event time.</li>
    +            <li>Only range predicates are valid time predicates.</li>
    +            <li>Non-time predicates must not access a time attribute.</li>
    --- End diff --
    @fhueske, I think the last rule about time attribute access could be removed now, right?

> Add support for windowed joins to Table API
> -------------------------------------------
>                 Key: FLINK-7798
>                 URL: https://issues.apache.org/jira/browse/FLINK-7798
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Table API & SQL
>    Affects Versions: 1.4.0
>            Reporter: Fabian Hueske
>            Assignee: Xingcan Cui
>            Priority: Blocker
>             Fix For: 1.4.0
> Currently, windowed joins on streaming tables are only supported through SQL.
> The Table API should support these joins as well. For that, we have to adjust the Table
API validation and translate the API into the respective logical plan. Since most of the code
should already be there for the batch Table API joins, this should be fairly straightforward.

This message was sent by Atlassian JIRA

View raw message