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https://issues.apache.org/jira/browse/CASSANDRA-6167?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13901459#comment-13901459
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Benedict commented on CASSANDRA-6167:
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It seems like this could be achieved today with static columns. Perhaps we
could permit filtering based on the value of a static column by comparison to a
non-static column, so that you have a static (time, aggregate), and you select
from non-static all values > time; compose with aggregate and update. Of
course, updating the value would need to be done via CAS to be safe.
Note I'm not endorsing this, but this certainly seems less bad than abusing the
type of the value column.
> Add end-slice termination predicate
> -----------------------------------
>
> Key: CASSANDRA-6167
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6167
> Project: Cassandra
> Issue Type: Improvement
> Components: API, Core
> Reporter: Tupshin Harper
> Priority: Minor
> Labels: ponies
>
> When doing performing storage-engine slices, it would sometimes be beneficial
> to have the slice terminate for other reasons other than number of columns or
> min/max cell name.
> Since we are able to look at the contents of each cell as we read it, this is
> potentially doable with very little overhead.
> Probably more challenging than the storage-engine implementation itself, is
> to come up with appropriate CQL syntax (Thrift, should we decide to support
> it, would be trivial).
> Two possibilities ar
> 1) special where function:
> SELECT pk,event from cf WHERE pk IN (1,5,10,11) AND
> partition_predicate({predicate})
> or a bigger language change, but i think one I prefer. more like:
> 2) SELECT pk,event from cf where pk IN (1,5,10,11) UNTIL PARTITION event
> {predicate}
> Neither feels perfect, but I do like the fact that the second one at least
> clearly states what it is intended to do.
> By using "UNTIL PARTITION", we could re-use the UNTIL keyword to handle other
> kinds of early-termination of selects that the coordinator might be able to
> do, such as stop retrieving additional rows from shards after a particular
> criterion was met.
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