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https://issues.apache.org/jira/browse/CASSANDRA-2474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13047296#comment-13047296
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T Jake Luciani commented on CASSANDRA-2474:
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Details of the current CF mapping in hive for static vs dynamic columns is here:

http://www.datastax.com/docs/0.8/brisk/about_hive#mapping-hive-external-tables-to-cassandra-column-families

HBase uses the Hive MAP<k,v> type to do this.

Search in http://wiki.apache.org/hadoop/Hive/HBaseIntegration for
"Hive MAP to HBase Column Family"

bq. Wouldn't it be fairly easy to create a MetaStore that wrapped any other 
MetaStore and taught it about the :row syntax?

Sure but this would still require a custom hive build so users of say EMR 
wouldn't be able to use it... We might be able to make a stand alone hive 
metastore service to support the syntax but it feels like a bad solution...

I don't see what is so bad about mapping each column and subcolumn so its own 
row like the Cassandra Hive driver does today.  This is the most natural fit 
for SQL.

Example: 
   key1 : { col1 : {subcol1:val1, subcol2: val2}}

maps to:

key, column, subcol, value
key1, col1, subcol1, val1
key1, col1, subcol2, val2


 


> CQL support for compound columns
> --------------------------------
>
>                 Key: CASSANDRA-2474
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-2474
>             Project: Cassandra
>          Issue Type: Sub-task
>          Components: API, Core
>            Reporter: Eric Evans
>              Labels: cql
>             Fix For: 1.0
>
>
> For the most part, this boils down to supporting the specification of 
> compound column names (the CQL syntax is colon-delimted terms), and then 
> teaching the decoders (drivers) to create structures from the results.

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