Using set type

Use the set data type to store unordered multiple items.

A set consists of a 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.

In the following example, a set called teams stores all the teams that a cyclist has been a member of during their career.

Procedure

Define teams in a table 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)