PostgreSQL Group By

The PostgreSQL GROUP BY is used when at least one of the aggregation functions(count, max, min, sum, avg) is used in a select.

SELECT column_name1, column_name2, function(column_name1)
FROM table_name
GROUP BY column_name1, column_name2

id	good_type	name	description	price
1	A	Car_1	Car 1 description	100
2	A	Car_2	Car 2 description	200
3	A	Car_3	Car 3 description	100
4	B	Boat_4	Boat 4 description	500
5	B	Boat_5	Boat 5 description	300
6	C	Train_1	Train 123 description	800

SELECT good_type, count(good_type) g_count
FROM goods
GROUP BY good_type