title: BigQuery: Is it posible to modify a table schema by adding a field within a record
body: <p><a href="https://cloud.google.com/bigquery/docs/manually-changing-schemas" rel="nofollow noreferrer">BigQuery manual</a> States that it is only possible to add a new field but not modify an existing one. My question is whether it is possible to add an existing field in to a RECORD field.
  Say the original schema is:</p>
  
  <pre><code>{"type":"RECORD","name":"record","mode":"REPEATED"
   "fields":[
      {"type":"STRING","name":"f1","mode":"NULLABLE"}
    ]
  }
  </code></pre>
  
  <p>And I would like to add f2 so the schema would be:</p>
  
  <pre><code>{"type":"RECORD","name":"record","mode":"REPEATED"
   "fields":[
      {"type":"STRING","name":"f1","mode":"NULLABLE"},
      {"type":"STRING","name":"f2","mode":"NULLABLE"}
    ]
  }
  </code></pre>
  
  <p>Is it possible?</p>