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: Core
Reporter: Jonathan Ellis
Fix For: 0.7.0
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.
