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https://issues.apache.org/jira/browse/CASSANDRA-1339?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12974438#action_12974438
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Jonathan Ellis commented on CASSANDRA-1339:
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bq. It's hard to think of a use case for which token order would be useful for 
GT[E] queries

Nevertheless we should keep column-ordering on result sets for CASSANDRA-1599

> add support for GT, GTE index expressions
> -----------------------------------------
>
>                 Key: CASSANDRA-1339
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1339
>             Project: Cassandra
>          Issue Type: New Feature
>          Components: API
>            Reporter: Jonathan Ellis
>             Fix For: 0.7.1
>
>
> this will require hitting every node in the cluster and merging results, 
> unlike with EQ.
> For instance, say we have the following index rows for some hypothetical 
> column C1:
> Node 1, ('' - M]
> 4: A G K 
> 5: B F J M
> Node 2, (M - '']
> 4: N P X
> 5: Q R T
> Because we store the index columns sorted in partitioner order, queries for 
> C1=4 can scan first node 1, then if insufficient data is found, proceed to 
> node 2.  But for GT or GTE queries we have to scan everyone and merge.  
> (Since we don't know what the next value after 4 is.  So an alternative would 
> be for each node to send back, along with the data for the first row, the row 
> key that comes next.  This would be very very messy.)
> Note that since we don't yet support range scans backwards, we can't support 
> LT or LTE queries.  The easiest workaround there would be to add a way to 
> specify that you want to create an index on the comparator, reversed.  This 
> is also worth doing for optimizations within normal columns -- see 
> CASSANDRA-1338.

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