Question

Have a table with about 500,000 rows. One of the columns is a string field.

Is there a way to get the set of all existing values of that string in PostgreSQL without having to request each row out of the database and add the values to a set manually?

Example:

first_name      last_name
will            i.am            
will            smith
britney         spears

The set of all existing values for “first_name” would be ['will', 'britney'].

Answer 1

SELECT DISTINCT first_name FROM people;

or

SELECT first_name FROM people GROUP BY first_name;