Many thanks Vladimir I am starting to see what you are talking about.
 
Yeah all I want to do is a simple Order By via SQL but having the column family 
setup using CLI to support that is a bit of a challenge for me at the moment 
since the two are at different levels but I prefer CLI for column family setup 
and just need an example of one at CLI level setup that translates to working 
Order By at CQL level.
 
Many Thanks!
-Tony
 

________________________________
 From: Vladimir Prudnikov <v.prudni...@gmail.com>
To: user@cassandra.apache.org 
Sent: Thursday, July 18, 2013 3:54 AM
Subject: Re: Intresting issue with getting Order By to work...
  


I'm not an expert, still learning C* but can tell something about your 
questions.

1) You have to understand that CQL row is not the same as row that C* uses to 
store data and which is accessible through the Trift interface. Primary key in 
terms of CQL is not the same as Row key. 

2) You have to be clear what you want to order: raw columns, rows or CQL rows. 
If you want to get ordered slices of raw rows you have to use Order Preserving 
Partitioner (which is not recommended, depends on you schema); If you want to 
order columns, it can be done easily; If you want to order CQL rows you have to 
have a composite primary key with at least 2 columns and you can order only by 
the second column in primary key. 

3) As far as I know column families created from CLI or Thrift will be 
accessible from CQL, but not opposite.

I hope experts will correct me if I'm wrong. 




On 17/07/2013, at 3:44 PM, Tony Anecito <adanec...@yahoo.com> wrote:
>>
>>> Hi All,
>>> 
>>> Well I got most everything working I wanted using Cassandra then discovered 
>>> I needed to use an Order By. I am using Cassandra 1.2.5.
>>> The use of Order By requires Primary Key which appears to be only supported 
>>> by by using CQL and not Cassandra-cli. So I dropped my table created uisng 
>>> CLI and used CQL and was able to create a "Table". But when I went
 to insert data that worked fine on the cli created table I now get an 
exception:
>>> Error while inserting 
>>> com.datastax.driver.core.exceptions.InvalidQueryException: Unknown 
>>> identifier type.
>>> 
>>> I read that thrift clients will not work with CQL created tables due to 
>>> extra things created by the CQL. If so how can I create Primary Keys and be 
>>> supported by thrift based clients??
>>> 
>>> I will post to Datastax the same question but trying to understand how to 
>>> resolve cli vs CQL issue like this. Seems like Cassandra-cli should support 
>>> creation of compound primary keys or CQL should create tables readable by 
>>> thrift based clients. Is there some meta column info people should add?
>>> Also CQL tables are not visible via cli.so I can not see details on what 
>>> was created by CQL and the cqlsh script has errors according to the latest 
>>> Python windows program I tried.
>>> 
>>> Thanks,
>>> -Tony
>>> 
>>> 
>>
>>
>>
>


-- 
Vladimir Prudnikov 

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