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https://issues.apache.org/jira/browse/KYLIN-2800?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Billy Liu reassigned KYLIN-2800:
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Assignee: zhengdong
> All dictionaries should be built based on the flat hive table
> -------------------------------------------------------------
>
> Key: KYLIN-2800
> URL: https://issues.apache.org/jira/browse/KYLIN-2800
> Project: Kylin
> Issue Type: Bug
> Reporter: zhengdong
> Assignee: zhengdong
> Attachments:
> 0001-KYLIN-2800-All-dictionaries-should-be-built-based-on.patch
>
>
> After KYLIN-2457, we still got wrong query result sometimes after a merging
> job finished.
> Finally, we realize the root cause is that we always use lookup table as
> source data to build dictionaries for FK columns.
> However, incremental lookup table doesn't mean sequential and incremental PK.
> If a new record inserted into the lookup table while its PK column does not
> have the max value, ID numbers in the new dictionary could be changed for
> those PK value larger than the newest one. What's more, using lookup table as
> source data for FK column's dictionary may has performance advantage for
> merging job, but also may encounter too big dictionary problem for large
> lookup tables. And we must add some validation rules to ensure the PK value
> sequential and incremental.
> On the another hand, we could just unify using the flat hive table as data
> source for all dictionaries.
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