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https://issues.apache.org/jira/browse/FLINK-11001?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16734222#comment-16734222
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Timo Walther commented on FLINK-11001:
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Updated exception message in master: 038dc0008f7b27c787e3ccba2204f3a2851dff7d
> Window rowtime attribute can't be renamed in Java
> -------------------------------------------------
>
> Key: FLINK-11001
> URL: https://issues.apache.org/jira/browse/FLINK-11001
> Project: Flink
> Issue Type: Bug
> Environment:
> Reporter: Hequn Cheng
> Assignee: Hequn Cheng
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.8.0
>
>
> Currently, we can rename window rowtime attribute like this in Scala:
> {code:java}
> table
> .window(Tumble over 2.millis on 'rowtime as 'w)
> .groupBy('w)
> .select('w.rowtime as 'rowtime, 'int.count as 'int)
> {code}
> However, an exception will be thrown if we use java(by changing the
> Expressions to String):
> {code:java}
> table
> .window(Tumble over 2.millis on 'rowtime as 'w)
> .groupBy('w)
> .select("w.rowtime as rowtime, int.count as int")
> {code}
> The Exception is:
> {code:java}
> org.apache.flink.table.api.ExpressionParserException: Could not parse
> expression at column 11: `,' expected but `a' found
> w.rowtime as rowtime, int.count as int
> {code}
>
> To solve the problem, we can add rename support in {{ExpressionParser}}.
> However, this may conflict with the design of source which use as before
> rowtime:
> {code:java}
> stream.toTable(
> tEnv,
> ExpressionParser.parseExpressionList("(b as b).rowtime, c as c, a as
> a"): _*)
> {code}
> Personally, I think we should keep the two consistent, so the final api would
> be:
> {code:java}
> // window case
> .select("w.rowtime as rowtime, int.count as int")
> // source case
> stream.toTable(
> tEnv,
> ExpressionParser.parseExpressionList("b.rowtime as b, c as c, a as a"):
> _*)
> {code}
> Any suggestions would be greatly appreciated!
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