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From: Marko Asplund <marko.asplund@gmail.com>
Date: Tue, 26 Mar 2013 18:08:05 +0200
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 <CANoUZR9+5C9DMy+cYhoSO59WcK8GOG3aH3a6GWZVhRocTeOtsA@mail.gmail.com>
Subject: CQL vs. non-CQL data models
To: user@cassandra.apache.org
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Hi,

I'm experimenting with CQL3 and the non-CQL Cassandra data access
methods through Astyanax client API. Being new to Cassandra I'm a bit
puzzled by differences between the CQL3 data model and the non-CQL
based data model exposed by the Astyanax client API.
Is this data model defined by Thrift? How closely does it reflect the
Cassandra internal data model?

Is there any documentation or other online pointers describing these
different data models?
Can I use both access methods for a particular column family?
Can a column family that was created using CQL have columns added to
it dynamically?
Can I add CQL required metadata to column families created using
Cassandra CLI later, so that they can be accessed via CQL?

I'm trying to access data created using CQL by using non-CQL based
access methods and vice versa and I'm confused about the following
behaviour:

- trying to use MutationBatch for modifying a rows in column family
that has been created using CQL results in:
  InvalidRequestException(why:Not enough bytes to read value of component 0)

- column family created using CQL is not visible via Cassandra CLI
	[default@test1] list employees1;
	employees1 not found in current keyspace.

- row data in column family created using Cassandra CLI is not
deserialized when read using cqlsh (select * from X)

- when accessing data in a column family that was created using CQL
	keyspace.prepareQuery(CF).getKey(id)
  the column names seem to be encoded strangely and can't be identified

- in CQL query a result row a call on Row.getKey() returns null


I'm using Cassandra v1.2.3 and Astyanax v1.56.31.

thanks,

marko