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
