A web service interface may receive a web service request that describes multiple objects. Each of the multiple objects may be associated with a common object, such as in a parent-child relationship. The web service can identify the common object and the multiple relationships between objects, and instead of creating duplicate versions of the common object, the web service can create a single record representing the common object in, for example, a database. Records for each of the multiple objects referring to the common object can reference the common object record in the database using, for example, foreign keys.