How did you create the table? 

Anyways that looks like a bug, I *think* they should go here 
http://code.google.com/a/apache-extras.org/p/cassandra-dbapi2/issues/list

Cheers

-----------------
Aaron Morton
Freelance Cassandra Developer
New Zealand

@aaronmorton
http://www.thelastpickle.com

On 24/01/2013, at 7:14 AM, Paul van Hoven <paul.van.ho...@googlemail.com> wrote:

> I try to access my local cassandra database via python. Therefore I
> installed db-api 2.0 and thrift for accessing the database. Opening
> and closing a connection works fine. But a simply query is not
> working:
> 
> The script looks like this:
> 
>    c = conn.cursor()
>    c.execute("""select * from users;""")
>    data = c.fetchall()
>    print "Query: select * from users; returned the following result:"
>    print str(data)
> 
> 
> The table users looks like this:
> qlsh:demodb> select * from users;
> 
> user_name | birth_year | gender | password | session_token | state
> -----------+------------+--------+----------+---------------+-------
>    jsmith |       null |   null |   secret |          null |  null
> 
> 
> 
> But when I try to execute it I get the following error:
> Open connection to localhost:9160 on keyspace demodb
> Traceback (most recent call last):
>  File 
> "/Users/Tom/Freelancing/Company/Python/ApacheCassandra/src/CassandraDemo.py",
> line 56, in <module>
>    perfromSimpleCQLQuery()
>  File 
> "/Users/Tom/Freelancing/Company/Python/ApacheCassandra/src/CassandraDemo.py",
> line 46, in perfromSimpleCQLQuery
>    c.execute("""select * from users;""")
>  File "/Library/Python/2.7/site-packages/cql/cursor.py", line 81, in execute
>    return self.process_execution_results(response, decoder=decoder)
>  File "/Library/Python/2.7/site-packages/cql/thrifteries.py", line
> 116, in process_execution_results
>    self.get_metadata_info(self.result[0])
>  File "/Library/Python/2.7/site-packages/cql/cursor.py", line 97, in
> get_metadata_info
>    name, nbytes, vtype, ctype = self.get_column_metadata(colid)
>  File "/Library/Python/2.7/site-packages/cql/cursor.py", line 104, in
> get_column_metadata
>    return self.decoder.decode_metadata_and_type(column_id)
>  File "/Library/Python/2.7/site-packages/cql/decoders.py", line 45,
> in decode_metadata_and_type
>    name = self.name_decode_error(e, namebytes,
> comptype.cql_parameterized_type())
>  File "/Library/Python/2.7/site-packages/cql/decoders.py", line 29,
> in name_decode_error
>    % (namebytes, expectedtype, err))
> cql.apivalues.ProgrammingError: column name '\x00\x00\x00' can't be
> deserialized as 'org.apache.cassandra.db.marshal.CompositeType':
> global name 'self' is not defined
> 
> I'm not shure if this is the right place to ask for: But am I doing
> here something wrong?

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