We've now seen a table with two columns in its primary key: a partition key and a clustering column. As it turns out, neither of these roles is limited to a single column. A table can define one or more partition key columns and zero or more clustering columns.
Clustering columns are not limited to one field as specified before. Let's take a look at how multiple clustering columns work and facilitate data ordering. To illustrate this, we will recreate our status updates table so that it is clustered by the date and time when the user updated their status:
CREATE TABLE "user_status_updates_by_datetime" ( "username" text, "status_date" date, "status_time" time, "body" text, PRIMARY KEY ("username", "status_date", "status_time") );
We have created a new table user_status_updates_by_datetime as shown next:
- Partition key:
username, which is a text field. - Clustering columns:
status_dateandstatus_time. Rows for a particular username are...