# joinByOneReverse

A joinByOneReverse field allows us to access the other side of a joinByOne relationship. Since this is the "other end" of the relationship, there is no editing interface. It is just a convenience allowing us to "see" the related object from the other point of view.

TIP

For backwards compatibility, you can set the idField option instead to match that in the other join, but this is confusing and hard to maintain. Just use reverseOf.

# Example

// Part of our schema for fabrics (see the joinByOne example)
{
  // No editing interface is currently offered, edit it from the other end
  //
  // Name is plural because more than one product might be joining to
  // each fabric; that's why `_products` will be an array
  name: '_products',
  type: 'joinByOneReverse',
  // Optional since our join name matches the other type's name
  withType: 'product',
  // Optional since there is only one join to fabrics in the other type
  reverseOf: '_fabric',
}

We can now see _product as a property of each fabric object that is related to a product.

# Settings

Property Type Default Description
name string Sets the name of the field in the database
label string Sets the label of the field that the user sees
required boolean false If true, the field is mandatory
contextual boolean false If true, it will prevent the field from appearing in a dialog box
type string Specifies the field type
readOnly boolean false If true, prevents the user from editing the field
help string Help text for the field that will appear with the field's label
htmlHelp string Help text with support for HTML markup
withType string The name of the related type, if it differs from the name of the join. If you do not set withType, then the name of the join must match the name of the related type, with a leading _ added.
ifOnlyOne boolean false If true, it will only carry out the join if the query that returned the original document returned only one document. This is useful if the joined information is only to be displayed on the show.html page of a piece, for instance, and you don't want the performance impact of loading it on the index.html page.

TIP

In documents with many joins in play, the ifOnlyOne option will avoid running through all the possible joins, and can be used to avoid a heavy performance impact in complex documents.