[jira] [Commented] (FLINK-9294) Improve type inference for UDFs with composite parameter or result type

["Timo Walther (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-9294?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16499844#comment-16499844 ] 

Timo Walther commented on FLINK-9294:
-------------------------------------

[~walterddr] I think you mean {{String[]}} instead of {{List<String>}} if the result should be an {{ObjectArrayTypeInfo}}, right?

> Improve type inference for UDFs with composite parameter or result type 
> ------------------------------------------------------------------------
>
>                 Key: FLINK-9294
>                 URL: https://issues.apache.org/jira/browse/FLINK-9294
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Table API &amp; SQL
>            Reporter: Rong Rong
>            Assignee: Rong Rong
>            Priority: Major
>
> Most of the UDF function signatures that includes composite types such as *{{MAP}}*, *{{ARRAY}}*, etc would require user to override *{{getParameterType}}* or *{{getResultType}}* method explicitly. 
> It should be able to resolve the composite type based on the function signature, such as:
> {code:java}
> public List<String> eval(Map<String, Integer> mapArg) {
>   //...
> }
> {code}
> should automatically resolve that:
> - *{{ObjectArrayTypeInfo<BasicTypeInfo.STRING>}}* to be the result type.
> - *{{MapTypeInfo<BasicTypeInfo.STRING, BasicTypeInfo.INTEGER>}}*  to be the parameter type.



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