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https://issues.apache.org/jira/browse/KUDU-686?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Grant Henke updated KUDU-686:
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    Target Version/s:   (was: 1.5.0)

> Delta apply optimizations
> -------------------------
>
>                 Key: KUDU-686
>                 URL: https://issues.apache.org/jira/browse/KUDU-686
>             Project: Kudu
>          Issue Type: Improvement
>          Components: perf, tablet
>    Affects Versions: M4.5
>            Reporter: David Alves
>            Priority: Trivial
>
> We currently iterate on each delta file several times, one for deletes and 
> then one for each one of the columns.
> It seems that, when selecting all the columns it would be more efficient to 
> apply the deltas to all columns at the same time. This might or might not be 
> advantageous depending on the number of columns projected. Todd also suggest 
> that whether this is an advantage also depends on whether there are 
> predicates being pushed down.
> We could likely also merge the updates and deletes into a single iteration or 
> at least avoid applying the mutations if the row will end up delete (right 
> now we still apply the updates even when we find that the row will be 
> deleted).



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