Incremento automático en PostgreSQL
ALTER TABLE temp ALTER COLUMN id
ADD GENERATED BY DEFAULT AS IDENTITY
JDBC
ALTER TABLE temp ALTER COLUMN id
ADD GENERATED BY DEFAULT AS IDENTITYCREATE SEQUENCE cateogry_id_seq;
ALTER TABLE category ALTER COLUMN category_id SET DEFAULT nextval('cateogry_id_seq');
By simply setting our id column as SERIAL with PRIMARY KEY attached, Postgres will handle all the complicated behind-the-scenes work and automatically increment our id column with a unique, primary key value for every INSERT .