create type t_user_type as enum ('superadmin','admin', 'owner', 'customer');

create sequence user_seq;

create table users (
id integer default nextval ('user_seq') primary key,
user_type t_user_type not null,
login varchar( 64 ) not null unique,
password varchar( 72 )not null,
display_name varchar( 255 ) not null unique,
description text not null,
reg_moment timestamp not null default now()
);

create or replace function sp_user ( t_user_type, varchar)

returns t_user_int

as $$
begin
grant all privileges to 'superadmin'
$$language sql