How do I modify fields inside the new PostgreSQL JSON datatype?

Question

With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can\'t find any examples of this in the postgresql documenta

Answer 1

For those who use mybatis, here is an example update statement:

    update quiz_execution set answer_data = jsonb_set(answer_data, concat('{', #{qid}, '}')::text[], #{value}::jsonb), updated_at = #{updatedAt}
    where id = #{id}

Params:

• qid, the key for field.
• value, is a valid json string, for field value,
  e.g converted from object to json string via jackson,