Learning Apache Cassandra - Second Edition

Static columns act like predefined joins

Now that we've explored the behavior of static columns, it's rather striking how similar the data model in users_with_status_updates is to the data model represented by users and user_status_updates taken together. In particular, both representations do the following:

• Associate multiple status updates with a single user
• Associate a single e-mail address and password with a single user
• Allow creating and accessing discrete user records, with or without associated status updates

The difference is simply the interface to the data model: are we working with one table, or two? It turns out that users_with_status_updates behaves very much like the result of an SQL LEFT JOIN of users and user_status_updates ...