text: -- Scenario:
  -- * One junction table record per unique pair of nodes (enforced by PK constraint)
  -- * No additional junction table columns
  
  drop schema if exists a cascade;
  create schema a;
  
  create table a.foo (
    foo_id integer primary key,
    foo_name text not null
  );
  
  create table a.bar (
    bar_id integer primary key,
    bar_name text not null
  );
  
  create table a.junction (
    j_foo_id integer references a.foo (foo_id),
    j_bar_id integer references a.bar (bar_id),
    primary key (j_foo_id, j_bar_id)
  );