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https://issues.apache.org/jira/browse/CASSANDRA-8519?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15083735#comment-15083735
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Robert Stupp edited comment on CASSANDRA-8519 at 1/5/16 8:41 PM:
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[~brianmhess] Java driver ticket is resolved and GA. Is that the solution?


was (Author: snazy):
[~brianmhess] Java driver ticket is resolved and GA. Also clients could query 
the schema tables. Is that a solution?

> Mechanism to determine which nodes own which token ranges without Thrift
> ------------------------------------------------------------------------
>
>                 Key: CASSANDRA-8519
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8519
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter:  Brian Hess
>            Priority: Minor
>
> Right now the only way to determine which nodes own which token ranges is via 
> the Thrift interface.  There is not a Java/CQL driver mechanism to determine 
> this.  Applications that make multiple connections to Cassandra to extract 
> data in parallel need this ability so they can split the data into pieces, 
> and it is reasonable to want those splits to be on token range boundaries.  
> Of course, once you split this way, you would want to route those queries to 
> nodes that own that token range / split, for efficiency.
> This applies for both Hadoop and Spark, but other applications, too.  Hadoop 
> and Spark currently use Thrift to determine this topology.
> Additionally, different replication strategies and replication factors result 
> in different token range ownership, so there will have to be a different 
> answer based on which keyspace is used. 
> It would be useful if this data was stored in a CQL table and could be simply 
> queried.  A suggestion would be to add a column to the 
> SYSTEM.SCHEMA_KEYSPACES table (maybe a complex Map of Host to a UDT that has 
> a List of (beginRange, endRange) pairs - as an example).  This table would 
> need to be updated on an ALTER KEYSPACE command or on a topology change 
> event.  This would allow the server(s) to hold this information and the 
> drivers could simply query it (as opposed to having each driver manage this 
> separately).



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