Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: Yes
Available in SharePoint Online
Each projected field is represented by a Field element. The maximum number of fields that can be included is defined as the difference between the maximum number of allowed fields in the primary list and the number of fields already in the primary list.
The following example shows how to add an additional field to the results returned by the query. The value of the List attribute is an alias to the foreign list. The alias is defined in a Join Element (View). The ShowField attribute must be set to the internal name of the foreign field. The Type is always ‘Lookup’.