[jira] [Commented] (FLINK-10834) TableAPI flatten() calculated value error

["Fabian Hueske (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-10834?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16681180#comment-16681180 ] 

Fabian Hueske commented on FLINK-10834:
---------------------------------------

Do you know what the SQL standard defines for non-deterministic functions (or how other DBMS handle the situation)?
Should they be evaluated just once per row?

If not, than this behavior might be actually fine.

This might also be a Calcite issue.

> TableAPI flatten() calculated value error
> -----------------------------------------
>
>                 Key: FLINK-10834
>                 URL: https://issues.apache.org/jira/browse/FLINK-10834
>             Project: Flink
>          Issue Type: Bug
>          Components: Table API & SQL
>            Reporter: sunjincheng
>            Assignee: Hequn Cheng
>            Priority: Major
>             Fix For: 1.7.1
>
>
> We have a UDF as follows:
> {code:java}
> object FuncRow extends ScalarFunction {
> def eval(v: Int): Row = { 
>   val version = "" + new Random().nextInt()          
>   val row = new Row(3)          
>   row.setField(0, version)          
>   row.setField(1, version)          
>   row.setField(2, version)          
>   row 
> }
> override def isDeterministic: Boolean = false
> override def getResultType(signature: Array[Class[_]]): TypeInformation[_] =
>  Types.ROW(Types.STRING, Types.STRING, Types.STRING)
> }
> {code}
> Do the following Query:
> {code:sql}
> val data = new mutable.MutableList[(Int, Long, String)]
>  data.+=((1, 1L, "Hi"))
>  val ds = env.fromCollection(data).toTable(tEnv, 'a, 'b,'c)
>  .select(FuncRow('a).flatten()).as('v1, 'v2, 'v3)
> {code}
> The result is : -1189206469,-151367792,1988676906
> The result expected by the user should be:  v1==v2==v3 .
> It looks the real reason is that there is no result of the reuse in codegen.
>  



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