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https://issues.apache.org/jira/browse/CASSANDRA-1704?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12928360#action_12928360
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Eric Evans commented on CASSANDRA-1704:
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Still chewing this over, but one reason this seems (somewhat )strange to me is 
that <COLUMNS> here is both of "a list of columns to include in the result" 
(like in an RDBMS), and "the query predicate" (or a portion of it anyway). I 
know that in a very real way those are kind of one and the same, but the SQL 
databases people are familiar with all have schema and the column names are 
identifiers. It's not just syntactically different, it's semantically different 
as well, and I wonder if this isn't going to set people up for 
misunderstandings.

Also, I'm not clear on whether you intended the <EXPRESSION> portion to remain 
the same; you chose a different syntax (less-SQL FWIW) to specifiy ranges and 
sets of columns than what I used in <EXPRESSION>.

> CQL reads (aka SELECT)
> ----------------------
>
>                 Key: CASSANDRA-1704
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1704
>             Project: Cassandra
>          Issue Type: Sub-task
>          Components: API
>    Affects Versions: 0.8
>            Reporter: Eric Evans
>            Priority: Minor
>             Fix For: 0.8
>
>   Original Estimate: 0h
>  Remaining Estimate: 0h
>
> Data access specification and implementation for CQL.  
> This corresponds to the following RPC methods:
> * get()
> * get_slice()
> * get_count()
> * multiget_slice()
> * multiget_count()
> * get_range_slices()
> * get_indexed_slices()
> The initial check-in to trunk/ uses a syntax that looks like:
> {code:SQL}
> SELECT (FROM)? <CF> [USING CONSISTENCY.<LVL>] WHERE <EXPRESSION> [ROWLIMIT X] 
> [COLLIMIT Y] [ASC|DESC]
> {code}
> Where:
> * <CF> is the column family name.
> * <EXPRESSION> consists of relations chained by the AND keyword.
> * <LVL> corresponds to one of the enum values in the RPC interface(s).
> What is still undone:
> * Support for indexes
> * Counts
> * Complete test coverage
> And of course, all of this is still very much open to further discussion.

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