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https://issues.apache.org/jira/browse/IOTDB-5735?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17705844#comment-17705844
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Chao Wang commented on IOTDB-5735:
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!https://clouddevops.huawei.com/vision-file-storage/api/file/download/upload-v2/2023/2/27/w00549253/389e4f6a848944948d30182a918d590a/image.png!
> The result of adding the distinct function to the align by device is
> incorrect.
> -------------------------------------------------------------------------------
>
> Key: IOTDB-5735
> URL: https://issues.apache.org/jira/browse/IOTDB-5735
> Project: Apache IoTDB
> Issue Type: Bug
> Components: mpp-cluster
> Affects Versions: 1.0.0
> Reporter: Chao Wang
> Priority: Major
>
> Currently, a storage group can contain a maximum of five RegionGroups. Data
> in different time periods of the same sequence is allocated to different
> RegionGroups using hash algorithm. In this case, data of the same sequence is
> stored in different Region Groups.
> According to the execution plan of the distinct + align by device syntax,
> distinct data is delivered to multiple region groups for execution and then
> summarized and returned. During the summarization, distinct processing is not
> performed. As a result, duplicate data exists between multiple region groups.
> !https://clouddevops.huawei.com/vision-file-storage/api/file/download/upload-v2/2023/2/27/w00549253/b70e9e8244d845f58c3891fe54c20571/image.png!
> !https://clouddevops.huawei.com/vision-file-storage/api/file/download/upload-v2/2023/2/27/w00549253/90246c3a906c44fc8422b839ba27c8d2/image.png!
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