> Now I am going to write a new application using cassandra so I started > reading > documentation in order to "model" the new db using all the new features and > not > reinventing the wheel. Some resources for CQL 3, it may match your needs. If not you can still use Thrift through your favourite client...
There have been a few articles on the DS blog http://www.datastax.com/dev/blog A talk at the conference by Eric http://www.datastax.com/events/cassandrasummit2012/presentations I did a webinar about it last month http://www.datastax.com/resources/webinars/collegecredit > 1) SCF are deprecated and I see that what it used to be a development concept > (use a CF and build a row name using ROW+SC name, if you want keep sorting > use > OPP) has become a Cassandra Concept (compund key). Yup (they have not been officially deprecated, it's just recommended that you do not use them). > > SELECT * FROM ctable WHERE basekey = ? and myvalue = ? ORDER BY extensionkey > DESC LIMIT 5 > I haven't been able to do it …. That looks ok, what was the error ? What cassandra version and what CQL version? > 2) Is Cassandra still schemaless? One thing I loved is that to create a new > column I didn't have to "alter" any cf before. > Trying CQL 3 I noticed that if I try to make an insert of a new "column" not > defined in schema I raised an exception. CQL 3 requires a schema, however altering the schema is easier. And in 1.2 will support concurrent schema modifications. Thrift API is still schema less. Cheers ----------------- Aaron Morton Freelance Cassandra Developer New Zealand @aaronmorton http://www.thelastpickle.com On 26/11/2012, at 12:21 AM, cbert...@libero.it wrote: > Hi all, > I'm in production with cassandra since version 0.6 then upgraded to 0.7 and > finally to 1.0. > If I look at my schema now it's "senseless" to be on 1.0 but many things > changed from 0.6 ... secondary indexes, counters, expiring columns and more. > Now I am going to write a new application using cassandra so I started > reading > documentation in order to "model" the new db using all the new features and > not > reinventing the wheel. > > So let's start with couple of questions ... sorry if stupid :-) > > 1) SCF are deprecated and I see that what it used to be a development concept > (use a CF and build a row name using ROW+SC name, if you want keep sorting > use > OPP) has become a Cassandra Concept (compund key). > Is it right? And more, can I avoid OPP when using compound keys since inside > partition key data are ordered on the remaining components of the primary key? > > finally I've tried to use the order by to sort data and it works -- but can > I > use order by and where clause on a secondary index together? > > CREATE TABLE ctable ( > basekey uuid, > extensionkey uuid, > myvalue varchar, > PRIMARY KEY (basekey, extensionkey) > ) > > SELECT * FROM ctable WHERE basekey = ? and myvalue = ? ORDER BY extensionkey > DESC LIMIT 5 > I haven't been able to do it .... > > 2) Is Cassandra still schemaless? One thing I loved is that to create a new > column I didn't have to "alter" any cf before. > Trying CQL 3 I noticed that if I try to make an insert of a new "column" not > defined in schema I raised an exception. > > Thanks in advance for any help > > Carlo > > > >
