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https://issues.apache.org/jira/browse/CASSANDRA-2474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13088958#comment-13088958
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Jonathan Ellis commented on CASSANDRA-2474:
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bq. Rather than trying to support all this flexibility on the fly in Hive, why 
don't we let users create transposed projections in the DML?

I like that idea, as the next best thing to finding a syntax that works well 
for both Hive and CQL.

So for CQL, I think we're close with the "transposed" idea.  As explained 
above, "we have "real" WHERE clauses we get all the benefits of regularity that 
implies."

I did note one problem with the transposed(x, y, z) syntax, though: you lose 
the ability to compose with other functions in the SELECT clause.  Currently 
that just means count(), but it's conceivable that we'd add scalar functions 
like sqrt(), or even aggregation like sum().

So I propose adding ".transposed" to the table name instead:

{noformat}
SELECT tweet_id, username, timestamp
FROM timeline.transposed 
WHERE user_id='jbellis'
LIMIT 50
{noformat}


> 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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