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https://issues.apache.org/jira/browse/ACCUMULO-3294?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15005803#comment-15005803
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Christopher Tubbs commented on ACCUMULO-3294:
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We already have the ability to manually modify individual properties. However,
it does require one to be familiar with how the serialization of iterators
occurs in a table's configuration.
[~kturner] and I were chatting about a related item the other day, regarding
ACCUMULO-4050 ideas, because we can't really offer consistency across scans for
iterator settings, even if we enable atomic updates to a batch of configuration
items. At the most, that buys us per scan session atomicity (within a tablet
server), but not per-scan atomicity. In that discussion, it was suggested that
we might want to urge users to prefer scan-time iterators over table-configured
iterators. And, the table-configured iterators that we do offer, should really
be used sparingly, reserved for privileged user decisions about how that table
should be presented (more like a "view" in an RDBMS, but with a 1-to-1 mapping
between the view and the dataset, instead of a many-to-1), with the full
understanding of the potential side-effects and pitfalls that alterations can
have due to lack of atomicity across the cluster.
Given all that, I'm not sure it's necessarily a good idea to add new APIs to
manage the table-configured iterators in ways that might enable users to shoot
themselves in the foot. The current solution to this use case is to remove an
entire iterator and reapply it with new configuration. That currently only
carries slightly less risk, though (much less after ACCUMULO-4050). This might
warrant further discussion. Obviously, if this is useful, I'm not going to be
opposed to it... but I think it warrants caution.
> Need mechanism to update iterator settings
> ------------------------------------------
>
> Key: ACCUMULO-3294
> URL: https://issues.apache.org/jira/browse/ACCUMULO-3294
> Project: Accumulo
> Issue Type: Improvement
> Components: client
> Reporter: John Vines
> Assignee: Jonathan Park
> Fix For: 1.8.0
>
> Attachments: bug3294.patch, bug3294.patch.1
>
>
> Currently our API supports attachIterator, removeIterator, and
> getIteratorSettings. There is no mechanism to directly change an iterators
> settings.
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