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https://issues.apache.org/jira/browse/DRILL-5527?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16017558#comment-16017558
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Julian Hyde commented on DRILL-5527:
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I think it would be best if we did this in the relational way. In the
relational model a column has only one value, and the update timestamp is a
column that belongs to the row.
So let's suppose that each time a columns value is changed, Drill makes an
entire new row appear. The row the same key as the previous row, but a new
timestamp or sequence number. Or perhaps the new row has a surrogate key that
is unique across the whole table.
This is how people manage SCDs in traditional kimbal data warehousing. I think
it is the simplest way to expose it for Drill users.
> Support for querying slowly changing dimensions of HBase/MapR-DB tables on
> TIMESTAMP/TIMERANGE/VERSION
> ------------------------------------------------------------------------------------------------------
>
> Key: DRILL-5527
> URL: https://issues.apache.org/jira/browse/DRILL-5527
> Project: Apache Drill
> Issue Type: New Feature
> Components: Storage - HBase
> Affects Versions: 1.10.0
> Reporter: Alan Fischer e Silva
>
> HBase and MapR-DB support versioning of cell values via timestamp, but today
> a Drill query only returns the most recent version of a cell.
> Being able to query an HBase/MapR-DB cell on it's version, timestamp or
> timerange would be a major improvement to the HBase storage plugin in order
> to support slowly changing dimensions.
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