[Postgresql] uuid 생성함수

uuid 생성방법에는 여러가지가 있다.

방법1.

CREATE OR REPLACE FUNCTION gen_uuid() 
RETURNS uuid stable language sql 
as 'SELECT md5(random()::text || clock_timestamp()::text)::uuid';

SELECT gen_uuid();

방법2

CREATE EXTENSION "uuid-ossp";

SELECT uuid_generate_v4();