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https://issues.apache.org/jira/browse/CARBONDATA-3347?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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QiangCai reassigned CARBONDATA-3347:
------------------------------------

    Assignee: QiangCai

> support SORT_COLUMNS modification
> ---------------------------------
>
>                 Key: CARBONDATA-3347
>                 URL: https://issues.apache.org/jira/browse/CARBONDATA-3347
>             Project: CarbonData
>          Issue Type: New Feature
>          Components: spark-integration
>            Reporter: QiangCai
>            Assignee: QiangCai
>            Priority: Major
>         Attachments: sort_columns modification.pdf
>
>
> *Background*
> Now SORT_COLUMNS can’t be modified after the table is created. If we want to 
> modify SORT_COLUMNS on this table, we need to create a new table and migrate 
> data. If the data is huge, the migration will take a long time and even 
> impact the user business. 
> SORT_SCOPE in table properties can be modified now. And we can specify new 
> SORT_SCOPE during data loading. Carbon index file will mark whether this 
> segment is sorted or not. So the different segments maybe have different 
> SORT_SCOPE.
> *Mo**tivation*
> After the table is created, the user can adjust SORT_SCOPE/SORT_COLUMNS 
> according to their business. History segments will still use old 
> SORT_SCOPE/SORT_COLUMNS, but the user also can resort old segments one by one 
> if need. 
> But we still suggest the user give a proper SORT_SCOPE/SORT_COLUMNS when they 
> create the table because the modification will take many resources to resort 
> data of old segments.
>  
> please check design doc for more detail.
> [^sort_columns modification.pdf]



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