Question

Just wanted to learn Cassandra and trying to convert RDBMS design to Canssandra.
Considered my app is being deployed in multiple Data centers.

DB Design :

       A) CF : USER
              1) email_id - primary key
              2) fullname
              3) organization - ( I didnt create a separate table for organization )

       B) CF : ORG_USER

             1) organization - Primary Key
             2) email_id

             Here, my intention is to get users belong to an organization.
             Here, I can make the organization in the user table as secondary index, but heard that, this may hit the performance.
             Could you please clarify me which is the better approach?

Thanks,
Baskar.S

Answer 1

Organization may be a good candidate for a secondary index as long as cardinality is low. In other words, if you have a lot of repeating values for organization, use a secondary index. If not, building the index manually (as you have indicated in your ORG_USER CF) is a fine approach.