Wide Rows - Data Model Design

[Check Peck]

I am trying to use wide rows concept in my data modelling design for
Cassandra. We are using Cassandra 2.0.6.

    CREATE TABLE test_data (
      test_id int,
      client_name text,
      record_data text,
      creation_date timestamp,
      last_modified_date timestamp,
      PRIMARY KEY (test_id, client_name, record_data)
    )

So I came up with above table design. Does my above table falls under the
category of wide rows in Cassandra or not?

And is there any problem If I have three columns in my  PRIMARY KEY? I
guess PARTITION KEY will be test_id right? And what about other two?

In this table, we can have multiple record_data for same client_name.

Query Pattern will be -

select client_name, record_data from test_data where test_id = 1;