create TABLE locations (
  id INTEGER PRIMARY KEY,
  x INTEGER NOT NULL,
  y INTEGER NOT NULL,
  z INTEGER NOT NULL,
  world INTEGER NOT NULL
)

create TABLE exits (
  id INTEGER PRIMARY KEY,
  to INTEGER REFERENCES locations(id),
  from INTEGER REFERENCES locations(id)
)

create TABLE observables (
  id INTEGER PRIMARY KEY,
  name TEXT NOT NULL,
  description TEXT NOT NULL
)

create TABLE inventories (
  id INTEGER PRIMARY KEY
)

create TABLE pools (
  id INTEGER PRIMARY KEY,
  type INTEGER NOT NULL
)