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-6196) Support dynamic schema in Table Function
Date Tue, 28 Mar 2017 01:41:41 GMT

    [ https://issues.apache.org/jira/browse/FLINK-6196?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15944370#comment-15944370
] 

ASF GitHub Bot commented on FLINK-6196:
---------------------------------------

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

    https://github.com/apache/flink/pull/3623#discussion_r108318419
  
    --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/functions/TableFunction.scala
---
    @@ -86,12 +90,79 @@ abstract class TableFunction[T] extends UserDefinedFunction {
         * @return [[Expression]] in form of a [[TableFunctionCall]]
         */
       final def apply(params: Expression*)(implicit typeInfo: TypeInformation[T]): Expression
= {
    -    val resultType = if (getResultType == null) {
    -      typeInfo
    +    buildTableFunctionCall(getClass.getSimpleName, typeInfo, params: _*)
    +  }
    +
    +  /**
    +    * Build a TableFunctionCall, a name and a sequence of params will determine a unique
    +    * [[TableFunctionCall]]
    +    *
    +    * @param name function name
    +    * @param implicitResultType If no result type returned, it will use this type.
    +    * @param params The input expressions
    +    * @return A unique [[TableFunctionCall]]
    +    */
    +  private[table] def buildTableFunctionCall(name: String,
    --- End diff --
    
    Can we move this to a util class? Since this is a user facing API class, we don't want
to expose such kind of thing.


> Support dynamic schema in Table Function
> ----------------------------------------
>
>                 Key: FLINK-6196
>                 URL: https://issues.apache.org/jira/browse/FLINK-6196
>             Project: Flink
>          Issue Type: Improvement
>          Components: Table API & SQL
>            Reporter: Zhuoluo Yang
>            Assignee: Zhuoluo Yang
>
> In many of our use cases. We have to decide the schema of a UDTF at the run time. For
example. udtf('c1, c2, c3') will generate three columns for a lateral view. 
> Most systems such as calcite and hive support this feature. However, the current implementation
of flink didn't implement the feature correctly.



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

Mime
View raw message