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https://issues.apache.org/jira/browse/CASSANDRA-4476?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14233123#comment-14233123
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Jeremiah Jordan commented on CASSANDRA-4476:
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bq. I don't understand the problem in your example. The query result seems
valid to me.
The problem is that (1, 6), (2, 6) are never going to be returned if you keep
paging through the query in that fashion.
bq. In addition, can you please explain how a query using only secondary
indexes such as select k from my_table where index1 = 5 and index2 > 10 allow
filtering retains token order?
What do you mean? It retains token order (and then clustering order) by the
results from "select k from my_table where index1 = 5" being in order, and
then filtering out anything with index2 > 10.
> Support 2ndary index queries with only inequality clauses (LT, LTE, GT, GTE)
> ----------------------------------------------------------------------------
>
> Key: CASSANDRA-4476
> URL: https://issues.apache.org/jira/browse/CASSANDRA-4476
> Project: Cassandra
> Issue Type: Improvement
> Components: API, Core
> Reporter: Sylvain Lebresne
> Assignee: Oded Peer
> Priority: Minor
> Labels: cql
> Fix For: 3.0
>
> Attachments: 4476-2.patch, 4476-3.patch, 4476-5.patch,
> cassandra-trunk-4476.patch
>
>
> Currently, a query that uses 2ndary indexes must have at least one EQ clause
> (on an indexed column). Given that indexed CFs are local (and use
> LocalPartitioner that order the row by the type of the indexed column), we
> should extend 2ndary indexes to allow querying indexed columns even when no
> EQ clause is provided.
> As far as I can tell, the main problem to solve for this is to update
> KeysSearcher.highestSelectivityPredicate(). I.e. how do we estimate the
> selectivity of non-EQ clauses? I note however that if we can do that estimate
> reasonably accurately, this might provide better performance even for index
> queries that both EQ and non-EQ clauses, because some non-EQ clauses may have
> a much better selectivity than EQ ones (say you index both the user country
> and birth date, for SELECT * FROM users WHERE country = 'US' AND birthdate >
> 'Jan 2009' AND birtdate < 'July 2009', you'd better use the birthdate index
> first).
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