[ 
https://issues.apache.org/jira/browse/FLINK-3943?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15356199#comment-15356199
 ] 

ASF GitHub Bot commented on FLINK-3943:
---------------------------------------

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

    https://github.com/apache/flink/pull/2169#discussion_r69048442
  
    --- Diff: 
flink-libraries/flink-table/src/test/scala/org/apache/flink/api/scala/batch/table/SetOperationsITCase.scala
 ---
    @@ -61,14 +62,28 @@ class UnionITCase(
         val ds1 = CollectionDataSets.getSmall3TupleDataSet(env).toTable(tEnv, 
'a, 'b, 'c)
         val ds2 = CollectionDataSets.getSmall3TupleDataSet(env).toTable(tEnv, 
'a, 'b, 'c)
     
    -    val unionDs = ds1.union(ds2).select('c)
    +    val minusDs = ds1.union(ds2).select('c)
    --- End diff --
    
    Why this change?


> Add support for EXCEPT (set minus)
> ----------------------------------
>
>                 Key: FLINK-3943
>                 URL: https://issues.apache.org/jira/browse/FLINK-3943
>             Project: Flink
>          Issue Type: New Feature
>          Components: Table API & SQL
>    Affects Versions: 1.1.0
>            Reporter: Fabian Hueske
>            Assignee: Ivan Mushketyk
>            Priority: Minor
>
> Currently, the Table API and SQL do not support EXCEPT.
> EXCEPT can be executed as a coGroup on all fields that forwards records of 
> the first input if the second input is empty.
> In order to add support for EXCEPT to the Table API and SQL we need to:
> - Implement a {{DataSetMinus}} class that translates an EXCEPT into a DataSet 
> API program using a coGroup on all fields.
> - Implement a {{DataSetMinusRule}} that translates a Calcite {{LogicalMinus}} 
> into a {{DataSetMinus}}.
> - Extend the Table API (and validation phase) to provide an except() method.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to