[ 
https://issues.apache.org/jira/browse/IOTDB-514?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Jialin Qiao closed IOTDB-514.
-----------------------------
    Fix Version/s: 0.10.0-SNAPSHOT
       Resolution: Fixed

> To support aggregation in the distributed version
> -------------------------------------------------
>
>                 Key: IOTDB-514
>                 URL: https://issues.apache.org/jira/browse/IOTDB-514
>             Project: Apache IoTDB
>          Issue Type: Improvement
>            Reporter: Tian Jiang
>            Assignee: Yuxin Zhang
>            Priority: Major
>              Labels: aggregation, distributed, pull-request-available, query
>             Fix For: 0.10.0-SNAPSHOT, master branch
>
>          Time Spent: 20m
>  Remaining Estimate: 0h
>
> The current aggregation cannot satisfy the needs in the distributed version, 
> to be specific, there are two points that should be satisfied:
> 1. The FirstValueAggrResult and LastValueAggrResult should also contain 
> timestamp.
> Without a timestamp, the coordinator node cannot tell the result from which 
> node is the true first/last.
> 2. An AggrResult should be able to merge with another. When we get 
> AggrResults from all nodes that participate in the query, these results 
> should be merged to generate a new result.
> To resolve the issue, you should:
> 1. Add a field `timestamp` in FirstValueAggrResult and LastValueAggrResult
> 2. Add an abstract method `merge(AggregateResult another)` in AggregateResult 
> and implement it properly.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to