The "Update a single row by ID and return the updated Model instance in 1 query:" section of the Recipes doc shows the following operation returning a single record:

const jennifer = await Person
  .query()
  .patch({firstName: 'Jenn', lastName: 'Lawrence'})
  .where('id', 1234)
  .returning('*');

console.log(jennifer.updatedAt); // NOW()-ish
console.log(jennifer.firstName); // "Jenn"

In actuality, this seems to return a list of records, i.e.jennifer.firstName will be undefined.