Using list type

A list is similar to a set; it groups and stores values. Unlike a set, the values stored in a list do not need to be unique and can be duplicated. In addition, a list stores the elements in a particular order and may be inserted or retrieved according to an index value.

Use the list data type to store data that has a possible many-to-many relationship with another column.

Prerequisite

Keyspace must exist

In the following example, a list called events stores all the race events on an upcoming calendar. The table is called upcoming_calendar. Each event listed in the list will have a text data type. Events can have several events occurring in a particular month and year, so duplicates can occur. The list can be ordered so that the races appear in the order that they will take place, rather than alphabetical order.

CQL

CREATE TABLE IF NOT EXISTS cycling.upcoming_calendar (
  year int,
  month int,
  events list<text>,
  PRIMARY KEY (year, month)
);

Result

 year | month | events
------+-------+---------------------------------------------
 2015 |     6 | ['Criterium du Dauphine', 'Tour de Suisse']
 2015 |     7 |                          ['Tour de France']

(2 rows)