set column
A set consists of a unordered group of elements with unique values.
Duplicate values will not be stored distinctly.
The values of a set are stored unordered, but will return the elements in sorted order when queried.
Use the set data type to store data that has a many-to-one relationship with another column.
Prerequisite
-
Keyspace must exist
In the following example, a set called teams stores all the teams that a cyclist has been a member of during their career.
The table is cyclist_career_teams.
Each team listed in the set will have a text data type.
The following example shows the table and the initial rows.
CREATE TABLE IF NOT EXISTS cycling.cyclist_career_teams (
id UUID PRIMARY KEY,
lastname text,
teams set<text>
); id | lastname | teams
--------------------------------------+-----------------+--------------------------------------------------------------------------------
----------------------
cb07baad-eac8-4f65-b28a-bddc06a0de23 | ARMITSTEAD | {'AA Drink - Leontien.nl', 'Boels-Dolmans Cycling Team', 'Te
am Garmin - Cervelo'}
5b6962dd-3f90-4c93-8f61-eabfa4a803e2 | VOS | {'Nederland bloeit', 'Rabobank Women Team', 'Rabobank-Liv Giant', 'Rabobank-Liv
Woman Cycling Team'}
1c9ebc13-1eab-4ad5-be87-dce433216d40 | BRAND | {'AA Drink - Leontien.nl', 'Leontien.nl', 'Rabobank-Liv Giant', 'Rabobank-Liv
Woman Cycling Team'}
e7cd5752-bc0d-4157-a80f-7523add8dbcd | VAN DER BREGGEN | {'Rabobank-Liv Woman Cycling Team', 'Sengers Ladies Cycling Tea
m', 'Team Flexpoint'}
(4 rows)