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https://issues.apache.org/jira/browse/HBASE-10885?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13956348#comment-13956348
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Andrew Purtell commented on HBASE-10885:
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bq. Delete.setCellVisibility() should be supported now.
Yes.
bq. And these labels passed here will be only a list of labels and not
visibility expressions like A|B!C?
No. Deletes should support visibility expressions just like Put, etc. The
supplied visibility expression is then associated with the delete marker(s).
Actually, scratch what I said above in the first comment. I think we can check
that the supplied expression does not exceed the maximal authorization set for
the user submitting the Delete in the preDelete hook and then store the delete
marker as a cell with a visibility expression tag and do the rest of the work
later, by hooking the compaction scanner. The big change then would be checking
for visibility expressions in tags on delete markers at compaction time. If we
find one, then we have to filter only the cells covered by the tombstone that
have a matching expression.
If we are not storing visibility expression terminals (LeafExpressionNodes) in
sorted order by ordinal we probably should consider it. (I don't think we are.)
Because e.g. A|B == B|A. It would be most efficient if we can simply do byte
comparison of serialized visibility expressions.
> Support visibility expressions on Deletes
> -----------------------------------------
>
> Key: HBASE-10885
> URL: https://issues.apache.org/jira/browse/HBASE-10885
> Project: HBase
> Issue Type: Improvement
> Affects Versions: 0.98.1
> Reporter: Andrew Purtell
> Fix For: 0.99.0, 0.98.2
>
>
> Accumulo can specify visibility expressions for delete markers. During
> compaction the cells covered by the tombstone are determined in part by
> matching the visibility expression. This is useful for the use case of data
> set coalescing, where entries from multiple data sets carrying different
> labels are combined into one common large table. Later, a subset of entries
> can be conveniently removed using visibility expressions.
> Currently doing the same in HBase would only be possible with a custom
> coprocessor. Otherwise, a Delete will affect all cells covered by the
> tombstone regardless if they are visible to the user issuing the delete or
> not. This is correct behavior in that no data spill is possible, but
> certainly could be surprising, and is only meant to be transitional. We
> decided not to support visibility expressions on Deletes to control the
> complexity of the initial implementation.
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