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Jonathan Ellis commented on CASSANDRA-1339: ------------------------------------------- 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. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.