text: create table accounts
  (
      id       serial primary key,
      login    varchar(255) not null unique,
      password varchar(255) not null
  );
  
  create table links
  (
      id          serial primary key,
      creator_id  int default null,
      real_link   varchar(255),
      key         varchar(255) unique,
      use_counter int default 0,
  
      constraint fk_creator
          foreign key (creator_id)
              references accounts (id)
  );