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https://issues.apache.org/jira/browse/FLINK-5654?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15937941#comment-15937941
 ] 

ASF GitHub Bot commented on FLINK-5654:
---------------------------------------

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

    https://github.com/apache/flink/pull/3590#discussion_r107613580
  
    --- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/nodes/datastream/DataStreamOverAggregate.scala
 ---
    @@ -119,6 +150,57 @@ class DataStreamOverAggregate(
     
       }
     
    +  def createTimeBoundedProcessingTimeOverWindow(inputDS: DataStream[Row]): 
DataStream[Row] = {
    +
    +    val overWindow: Group = logicWindow.groups.get(0)
    +    val partitionKeys: Array[Int] = overWindow.keys.toArray
    +    val namedAggregates: Seq[CalcitePair[AggregateCall, String]] = 
generateNamedAggregates
    +
    +    val index = 
overWindow.lowerBound.getOffset.asInstanceOf[RexInputRef].getIndex
    +    val count = input.getRowType().getFieldCount()
    +    val lowerboundIndex = index - count
    +    
    +    
    +    val time_boundary = 
logicWindow.constants.get(lowerboundIndex).getValue2 match {
    +      case _: java.math.BigDecimal => 
logicWindow.constants.get(lowerboundIndex)
    +         .getValue2.asInstanceOf[java.math.BigDecimal].longValue()
    +      case _ => throw new TableException("OVER Window boundaries must be 
numeric")
    +    }
    +
    +     // get the output types
    +    val rowTypeInfo = 
FlinkTypeFactory.toInternalRowTypeInfo(getRowType).asInstanceOf[RowTypeInfo]
    +         
    +    val result: DataStream[Row] =
    +        // partitioned aggregation
    +        if (partitionKeys.nonEmpty) {
    +          
    +          val processFunction = 
AggregateUtil.CreateTimeBoundedProcessingOverProcessFunction(
    +            namedAggregates,
    +            inputType,
    +            time_boundary)
    +          
    +          inputDS
    +          .keyBy(partitionKeys: _*)
    +          .process(processFunction)
    +          .returns(rowTypeInfo)
    +          .name(aggOpName)
    +          .asInstanceOf[DataStream[Row]]
    +        } else { // non-partitioned aggregation
    +          val processFunction = 
AggregateUtil.CreateTimeBoundedProcessingOverProcessFunction(
    --- End diff --
    
    Hi @rtudoran, IMO `MapState` is the better option. Have a look at this 
[comment](https://github.com/apache/flink/pull/3574#issuecomment-288646109) 
where I explain the benefits of the `MapState` approach.
    
    It is true, that we need to read all keys if we use `MapState`, but 1) this 
is only read/deserialization 2) it is cheap `Long` values. The huge advantage 
of `MapState` is that we only have to reading and writing relevant `Row` values.
    
    With `ListState` and `ValueState` we always have to read and write all 
`Row` values.
    
    The complexity of operating on the deserialized structures should be very 
similar for all approaches and be negligible compared to the cost of 
de/serializing (which includes object instantiations)


> Add processing time OVER RANGE BETWEEN x PRECEDING aggregation to SQL
> ---------------------------------------------------------------------
>
>                 Key: FLINK-5654
>                 URL: https://issues.apache.org/jira/browse/FLINK-5654
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Table API & SQL
>            Reporter: Fabian Hueske
>            Assignee: radu
>
> The goal of this issue is to add support for OVER RANGE 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() RANGE BETWEEN INTERVAL '1' 
> HOUR PRECEDING AND CURRENT ROW) AS sumB,
>   MIN(b) OVER (PARTITION BY c ORDER BY procTime() RANGE BETWEEN INTERVAL '1' 
> HOUR 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-5657)
> - 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).



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