[ 
https://issues.apache.org/jira/browse/FLINK-5653?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15926368#comment-15926368
 ] 

ASF GitHub Bot commented on FLINK-5653:
---------------------------------------

Github user sunjincheng121 commented on a diff in the pull request:

    https://github.com/apache/flink/pull/3547#discussion_r106193738
  
    --- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/nodes/datastream/DataStreamOverAggregate.scala
 ---
    @@ -17,34 +17,38 @@
      */
     package org.apache.flink.table.plan.nodes.datastream
     
    -import org.apache.calcite.plan.{RelOptCluster, RelTraitSet}
    +import org.apache.calcite.plan.{ RelOptCluster, RelTraitSet }
     import org.apache.calcite.rel.`type`.RelDataType
     import org.apache.calcite.rel.core.AggregateCall
    -import org.apache.calcite.rel.{RelNode, RelWriter, SingleRel}
    +import org.apache.calcite.rel.{ RelNode, RelWriter, SingleRel }
     import org.apache.flink.api.java.typeutils.RowTypeInfo
     import org.apache.flink.streaming.api.datastream.DataStream
    -import org.apache.flink.table.api.{StreamTableEnvironment, TableException}
    +import org.apache.flink.table.api.{ StreamTableEnvironment, TableException 
}
     import org.apache.flink.table.calcite.FlinkTypeFactory
     import org.apache.flink.table.runtime.aggregate._
     import org.apache.flink.table.plan.nodes.OverAggregate
     import org.apache.flink.types.Row
     import org.apache.calcite.rel.core.Window
     import org.apache.calcite.rel.core.Window.Group
    -import java.util.{List => JList}
    +import java.util.{ List => JList }
     
     import org.apache.flink.table.functions.{ProcTimeType, RowTimeType}
     import org.apache.flink.table.runtime.aggregate.AggregateUtil.CalcitePair
    +import org.apache.calcite.sql.`type`.BasicSqlType
    +import org.apache.flink.streaming.api.functions.windowing.WindowFunction
    +import org.apache.flink.streaming.api.windowing.windows.GlobalWindow
    +import org.apache.flink.api.java.tuple.Tuple
     
     class DataStreamOverAggregate(
    -    logicWindow: Window,
    -    cluster: RelOptCluster,
    -    traitSet: RelTraitSet,
    -    inputNode: RelNode,
    -    rowRelDataType: RelDataType,
    -    inputType: RelDataType)
    -  extends SingleRel(cluster, traitSet, inputNode)
    -  with OverAggregate
    -  with DataStreamRel {
    +  logicWindow: Window,
    +  cluster: RelOptCluster,
    +  traitSet: RelTraitSet,
    +  inputNode: RelNode,
    +  rowRelDataType: RelDataType,
    +  inputType: RelDataType)
    +    extends SingleRel(cluster, traitSet, inputNode)
    --- End diff --
    
    Indent 2 space.


> Add processing time OVER ROWS BETWEEN x PRECEDING aggregation to SQL
> --------------------------------------------------------------------
>
>                 Key: FLINK-5653
>                 URL: https://issues.apache.org/jira/browse/FLINK-5653
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Table API & SQL
>            Reporter: Fabian Hueske
>            Assignee: Stefano Bortoli
>
> The goal of this issue is to add support for OVER ROWS aggregations on 
> processing time streams to the SQL interface.
> Queries similar to the following should be supported:
> {code}
> SELECT 
>   a, 
>   SUM(b) OVER (PARTITION BY c ORDER BY procTime() ROWS BETWEEN 2 PRECEDING 
> AND CURRENT ROW) AS sumB,
>   MIN(b) OVER (PARTITION BY c ORDER BY procTime() ROWS BETWEEN 2 PRECEDING 
> AND CURRENT ROW) AS minB
> FROM myStream
> {code}
> The following restrictions should initially apply:
> - All OVER clauses in the same SELECT clause must be exactly the same.
> - The PARTITION BY clause is optional (no partitioning results in single 
> threaded execution).
> - The ORDER BY clause may only have procTime() as parameter. procTime() is a 
> parameterless scalar function that just indicates processing time mode.
> - UNBOUNDED PRECEDING is not supported (see FLINK-5656)
> - FOLLOWING is not supported.
> The restrictions will be resolved in follow up issues. If we find that some 
> of the restrictions are trivial to address, we can add the functionality in 
> this issue as well.
> This issue includes:
> - Design of the DataStream operator to compute OVER ROW aggregates
> - Translation from Calcite's RelNode representation (LogicalProject with 
> RexOver expression).



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

Reply via email to