[jira] [Commented] (FLINK-4242) Improve validation exception messages

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

    [ https://issues.apache.org/jira/browse/FLINK-4242?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15390749#comment-15390749 ] 

GaoLun commented on FLINK-4242:
-------------------------------

Yes, currently some messages of table exception aren't readable and clear for the users. 
I will open a PR for this issue.

> Improve validation exception messages
> -------------------------------------
>
>                 Key: FLINK-4242
>                 URL: https://issues.apache.org/jira/browse/FLINK-4242
>             Project: Flink
>          Issue Type: Improvement
>          Components: Table API & SQL
>    Affects Versions: 1.1.0
>            Reporter: Till Rohrmann
>            Priority: Minor
>
> The Table API's validation exceptions could be improved to be more meaningful for users. For example, the following code snippet:
> {code}
> Table inputTable = tableEnv.fromDataStream(env.fromElements(
>                 Tuple3.of(1, "a", 1.0),
>                 Tuple3.of(2, "b", 2.0),
>                 Tuple3.of(3, "c", 3.0)), "a, b, c");
> inputTable.select("a").where("!a");
> {code}
> fails correctly. However, the validation exception message says "Expression !('a) failed on input check: Not only accepts child of Boolean Type, get Integer". I think it could be changed such that it says: "The not operator requires a boolean input but "a" is of type integer." or something similar.



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