[
https://issues.apache.org/jira/browse/PIG-2119?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13048748#comment-13048748
]
Daniel Dai commented on PIG-2119:
---------------------------------
LOGenerate is the only sink in nested plan. This is one of the basic assumption
we made throughout logical plan. To solve the issue above, we need to prune the
dangling branch before proceed.
> DuplicateForEachColumnRewrite makes assumptions about the position of
> LOGGenerate in the plan
> ---------------------------------------------------------------------------------------------
>
> Key: PIG-2119
> URL: https://issues.apache.org/jira/browse/PIG-2119
> Project: Pig
> Issue Type: Bug
> Reporter: Gianmarco De Francisci Morales
>
> The input:
> {code}
> grunt> cat b.txt
> a 11
> b 3
> c 10
> a 12
> b 10
> c 15
> {code}
> The script:
> {code}
> a = load 'b.txt' AS (id:chararray, num:int);
> b = group a by id;
> c = foreach b {
> d = order a by num DESC;
> n = COUNT(a);
> e = limit d 1;
> generate n;
> }
> {code}
> The exception:
> {code}
> Caused by: java.lang.ClassCastException:
> org.apache.pig.newplan.logical.relational.LOLimit cannot be cast to
> org.apache.pig.newplan.logical.relational.LOGenerate
> at
> org.apache.pig.newplan.logical.rules.DuplicateForEachColumnRewrite$DuplicateForEachColumnRewriteTransformer.check(DuplicateForEachColumnRewrite.java:87)
> at
> org.apache.pig.newplan.optimizer.PlanOptimizer.optimize(PlanOptimizer.java:108)
> {code}
> I know the script is a bit pointless, but I was just testing and modifying
> the script bit by bit.
> If I remove the limit in any case I get the same exception but with LOSort.
> The problem, I think, is that the rule assumes there is only 1 sink in the
> nested block and that this sink is a LOGenerate.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
