[jira] [Commented] (FLINK-3579) Improve String concatenation

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-3579?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15221548#comment-15221548 ] 

ASF GitHub Bot commented on FLINK-3579:
---------------------------------------

Github user ramkrish86 commented on a diff in the pull request:

    https://github.com/apache/flink/pull/1821#discussion_r58191031
  
    --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/api/table/expressions/ExpressionParser.scala ---
    @@ -59,6 +59,8 @@ object ExpressionParser extends JavaTokenParsers with PackratParsers {
               Literal(str.toInt)
             } else if (str.endsWith("f") | str.endsWith("F")) {
               Literal(str.toFloat)
    +        } else if (str.endsWith(".")) {
    --- End diff --
    
    @tillrohrmann 
    This '.' related change I think I need more time to understand how this parser works. So for this PR can i only handle the string concat part. I have ensured that 42+a+b or a + b + 42 works fine. 


> Improve String concatenation
> ----------------------------
>
>                 Key: FLINK-3579
>                 URL: https://issues.apache.org/jira/browse/FLINK-3579
>             Project: Flink
>          Issue Type: Bug
>          Components: Table API
>            Reporter: Timo Walther
>            Assignee: ramkrishna.s.vasudevan
>            Priority: Minor
>
> Concatenation of a String and non-String does not work properly.
> e.g. {{f0 + 42}} leads to RelBuilder Exception
> ExpressionParser does not like {{f0 + 42.cast(STRING)}} either.



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