PostgreSQL Distinct

PostgreSQL Distinct

The PostgreSQL DISTINCT is used to eliminate duplicate records from a table or a query.

Distinct syntax

-- select distinct column records from table
SELECT DISTINCT column_name FROM table_name

-- select specific columns 
SELECT DISTINCT column_name1, column_name2 FROM table_name

Distinct example

Goods table

id good_type name description price insert_date
1 A Car_1 Car 1 description 100 2018-07-21 08:45:57.311809
2 A Car_2 Car 2 description 200 2018-07-21 08:45:57.311809
3 A Car_3 Car 3 description 100 2018-07-21 08:45:57.311809
4 B Boat_4 Boat 4 description 500 2018-07-21 08:45:57.311809
5 B Boat_5 Boat 5 description 300 2018-07-21 08:45:57.311809
6 C Train_1 Train 123 description 800 2018-07-21 08:45:57.311809
SELECT DISTINCT good_type FROM goods;

Result

good_type
B
C
A
SELECT DISTINCT good_type, price FROM goods;

Result

good_type price
B 500
B 300
A 200
C 800
A 100