How to sort/order with extraFields in aldeed:tabular?

help
1

I would like to sort/order with extraFields.

TabularTables.Books = new Tabular.Table({
  name: "Books",
  collection: Books,
  order: [[2, "desc"]],
  columns: [
    {data: "title", title: "Title"},
    {data: "author", title: "Author"}
  ],
 extraFields: ['otherField']
......

Please help me.