[
https://issues.apache.org/jira/browse/FLINK-7599?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16704253#comment-16704253
]
ASF GitHub Bot commented on FLINK-7599:
---------------------------------------
dianfu commented on a change in pull request #7177: [FLINK-7599] [table]
Support for aggregates in MATCH_RECOGNIZE
URL: https://github.com/apache/flink/pull/7177#discussion_r237724165
##########
File path:
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/MatchCodeGenerator.scala
##########
@@ -42,6 +50,90 @@ import scala.collection.mutable
/**
* A code generator for generating CEP related functions.
*
+ * Aggregates are generated as follows:
+ * 1. all aggregate [[RexCall]]s are grouped by corresponding pattern variable
+ * 2. even if the same aggregation is used multiple times in an expression
+ * (e.g. SUM(A.price) > SUM(A.price) + 1) it will be calculated once. To
do so [[AggBuilder]]
+ * keeps set of already seen different aggregation calls, and reuses the
code to access
+ * appropriate field of aggregation result
+ * 3. after translating every expression (either in [[generateCondition]] or
in
+ * [[generateOneRowPerMatchExpression]]) there will be generated code for
+ * * [[GeneratedFunction]], which will be an inner class
Review comment:
code format
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
> Support aggregation functions in the define and measures clause of
> MatchRecognize
> ---------------------------------------------------------------------------------
>
> Key: FLINK-7599
> URL: https://issues.apache.org/jira/browse/FLINK-7599
> Project: Flink
> Issue Type: Sub-task
> Components: CEP, Table API & SQL
> Reporter: Dian Fu
> Assignee: Dawid Wysakowicz
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.8.0
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
