Thanks,

worked a treat !

Andy


________________________________
From: DuyHai Doan <[email protected]>
Sent: 15 February 2014 18:51
To: [email protected]
Subject: Re: CQL get unique row keys ?

Hello Andy

 Since C* 2.0.1 it is possible to list all distinct partition keys (not 
clustering keys) with: SELECT DISTINCT pk FROM ....

 More info on the feature here: 
https://issues.apache.org/jira/browse/CASSANDRA-4536

 This query is quite efficient because the key cache is used most of the time.

 Regards

 Duy Hai DOAN



On Sat, Feb 15, 2014 at 6:05 PM, Andrew Cobley 
<[email protected]<mailto:[email protected]>> wrote:
I may be missing something here, but is there a way in cql to get all unique 
row keys in a column family(table) ?

I've created a table like this:

CREATE TABLE totp (
artist varchar,
track varchar,
 appearance_type varchar,
 PRIMARY KEY ((artist),track)
) WITH CLUSTERING ORDER BY (track asc);

and populated it with data.  As you can imagine, each artist can have multiple 
tracks .  Doing:

Select * from totp; will produce something like (with more artists of course)

                   The Tony Rich Project |                             Nobody 
Knows |             P/A
                            Telly Savalas |                                     
  If |           PROMO
                             Alice Cooper |                                  
Elected |            DISC
                             Alice Cooper |                             Hello 
Hooray |           PROMO
                             Alice Cooper |                               Hey 
Stupid |           Promo
                             Alice Cooper |                          Lost In 
America |             P/A
                             Alice Cooper |                      No More 
Mr.Nice Guy |            DISC
                             Alice Cooper |                                   
Poison |           Promo
                             Alice Cooper |                             
School's Out |         P/A V/T
                             Alice Cooper |                              
Schools Out |             P/A
                             Alice Cooper |                       Teenage 
Lament '74 |            DISC
                  Blackstreet Feat Dr.Dre |                               No 
Diggity |             P/A
                                     Nena |                           99 
Luftballons |           Promo
                                     Nena |                          99 Red 
Balloons |             P/A
and Select artist from totp; would produce:

                    The Tony Rich Project
                            Telly Savalas
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                             Alice Cooper
                  Blackstreet Feat Dr.Dre
                                     Nena
                                     Nena

But of course what I really want is just the row keys
    The Tony Rich Project
                            Telly Savalas
                             Alice Cooper
                  Blackstreet Feat Dr.Dre
                                     Nena

Any idea if I can do this in CQL ?

Andy


The University of Dundee is a registered Scottish Charity, No: SC015096


The University of Dundee is a registered Scottish Charity, No: SC015096

Reply via email to