CREATE TABLE users (
  id            UUID            NOT NULL DEFAULT uuid_generate_v4() PRIMARY KEY,
  username      varchar(255)      NOT NULL,
  password      char(128)         NOT NULL,
  phone         varchar(255)      NOT NULL
);
-- 索引
CREATE INDEX index_users_on_username on users (username);
-- 唯一
CREATE UNIQUE INDEX index_users_on_phone on users (phone);

1. 在pgsql中安装扩展
   create extension "uuid-ossp" ;
2. 查询
   select uuid_generate_v4()

pgsql中uuid使用