Altering of types is not allowed

[Ryan Flynn]

Hi,

I’m fairly new to this and am attempting a pretty basic “change column type” 
example.  I’m receiving an error saying InvalidRequest: Error from server: 
code=2200 [Invalid query] message="Altering of types is not allowed" upon 
attempting to change any column type.

For example, from the DataStax ALTER TABLE CQL Reference 
Page<https://docs.datastax.com/en/cql/3.1/cql/cql_reference/alter_table_r.html>,
 (assuming already USEing a particular keyspace)

                CREATE TABLE users (user_name varchar PRIMARY KEY, bio ascii);

Then,

                ALTER TABLE users ALTER bio TYPE text;

Results in the error mentioned above.  I saw this JIRA 
Issue<https://issues.apache.org/jira/browse/CASSANDRA-13141>, and it’s the only 
thing I can find related to this problem, although that use case is specific to 
changing time-related types.  Could someone tell me if I’m doing something 
wrong or if this is a known issue?  I originally saw this on version 3.10, then 
tried using 3.0.12, and the issue is present there as well.  And I’m just 
running these via cqlsh, if it makes any difference.

Thanks in advance!

Ryan Flynn