Check out example codes for "faunadb update". It will help you in understanding the concepts better.

Code Example 1

client.query(
  q.Update(
    q.Ref(q.Collection('spells'), '181388642581742080'),
    {
      data: {
        name: 'Mountain\'s Thunder',
        cost: null,
      },
    },
  )
)
.then((ret) => console.log(ret))

Code Example 2

Update( ref, param_object )

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