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https://issues.apache.org/jira/browse/CASSANDRA-348?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12740142#action_12740142
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Jonathan Ellis commented on CASSANDRA-348:
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Node selection code is working as designed but it is not quite what getKeyRange
expects.
The node selection is "pick the node whose token is nearest to the decorated
key, _always rounding up_." so what you end up with here is 3 range sections:
["", 000000000] node A (the one with token 00000000)
(00000000, 88888888] node B (the one with token 88888888)
(88888888, infinity) node A again
so, key 00 goes on node A, but 01-88 go on node B. then 09-ff go on node A
again.
we could hack around this in getKeyRange but it seems like the Right Fix is to
make it so A has ['', 88888888) and B has [88888888, inf), no?
what do you think, Jun? is there any inherent advantage to "round up" instead
of "round down" that I have forgotten?
[yeah, we're ignoring RackAware for now]
> Range scan over two nodes returns wrong data
> --------------------------------------------
>
> Key: CASSANDRA-348
> URL: https://issues.apache.org/jira/browse/CASSANDRA-348
> Project: Cassandra
> Issue Type: Bug
> Affects Versions: 0.4
> Reporter: Mark Robson
> Attachments: 348.diff, setup.cas
>
>
> I've got two nodes with tokens 00000000 and 88888888. I add 16 rows in which
> are spread over them, then do a key range scan.
> I can scan part of the range successfully, but if I try to scan the entire
> range of keys (0-f) then I get unexpected results
> ./Cassandra-remote -h localhost:9160 get_key_range Keyspace1 Standard1 0 31
> 1000
> ['00', '01', '10', '11', '20', '21', '30', '31']
> ./Cassandra-remote -h localhost:9160 get_key_range Keyspace1 Standard1 3 81
> 1000
> ['30', '31', '40', '41', '50', '51', '60', '61', '70', '71', '80', '81']
> ./Cassandra-remote -h localhost:9160 get_key_range Keyspace1 Standard1 7 b1
> 1000
> ['70', '71', '80', '81', '90', '91', 'a0', 'a1', 'b0', 'b1']
> ./Cassandra-remote -h localhost:9160 get_key_range Keyspace1 Standard1 a g
> 1000
> ['a0', 'a1', 'b0', 'b1', 'c0', 'c1', 'd0', 'd1', 'e0', 'e1', 'f0', 'f1']
> All of which returned as I expected.
> But when I range scan the whole lot (0-g) then I get:
> ./Cassandra-remote -h localhost:9160 get_key_range Keyspace1 Standard1 0 g
> 1000
> [ '00',
> '90',
> '91',
> 'a0',
> 'a1',
> 'b0',
> 'b1',
> 'c0',
> 'c1',
> 'd0',
> 'd1',
> 'e0',
> 'e1',
> 'f0',
> 'f1']
> Where have 01-81 gone?
> I'll attach the data loading script.
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