More background http://www.datastax.com/dev/blog/thrift-to-cql3
> So does this mean that in CQL 3 an explicit schema is absolutely
> mandatory?
Not really, it sort of depends on your view.
Lets say this is a "schema free" CF definition in CLI
create column family clicks
with key_validation_class = UTF8Type
and comparator = DateType
and default_validation_class = UTF8Type
It could be used for wide rows with lots of columns, where the name is a date.
As the article at the top says, this CQL 3 DDL is equivalent:
CREATE TABLE clicks (
key text,
column1 timestamp,
value text,
PRIMARY KEY (key, column)
) WITH COMPACT STORAGE
This creates a single row inside C*, column name is a date. The difference is
CQL 3 pivots this one "storage engine" row into multiple CQL 3 rows. (See
article)
So far so good. Let's add some schema:
CREATE TABLE clicks (
user_id text,
click_time timestamp,
click_url text,
PRIMARY KEY (user_id, click_time)
) WITH COMPACT STORAGE
That's functionally the same but has some more schema in it. It tells CQL 3
that the label to use for the name of a column is "click_time". Previously the
label was "column1".
> It's now impossible (within CQL) to add new
> (non-primary-key) columns only for individual rows implicitly with
> DML-queries (insert/update)?.
Is your use case covered in the article above ?
Cheers
-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com
On 30/10/2012, at 2:31 AM, Timmy Turner <[email protected]> wrote:
> Thank you! That article helps clear up a lot of my confusion about the
> changes between CQL 2 and 3, since I was wondering how to
> access/manipulate CompositeType/DynamicCompositeType columns through
> CQL.
>
> So does this mean that in CQL 3 an explicit schema is absolutely
> mandatory? It's now impossible (within CQL) to add new
> (non-primary-key) columns only for individual rows implicitly with
> DML-queries (insert/update)?.
>
>
>
>
> 2012/10/29 Sylvain Lebresne <[email protected]>:
>> CQL3 does absolutely allow dynamic column families, but does it
>> differently from CQL2. See
>> http://www.datastax.com/dev/blog/cql3-for-cassandra-experts.
>>
>> --
>> Sylvain
>>
>> On Mon, Oct 29, 2012 at 12:34 PM, Timmy Turner <[email protected]> wrote:
>>> Does CQL3 not allow dynamic columns (column names) any more?
