Anypoint DataGraph Terminology
The following terms, some of which come from the GraphQL lexicon, are useful for understanding how Anypoint DataGraph works.
| Term | Usage | 
|---|---|
API schema  | 
Generated by Anypoint DataGraph from your API specification in RAML or OAS, an API schema contains a collection of the GET resources and entities that you’ve defined in your API specification, and the relationships between them.  | 
Unified schema  | 
The unified schema is a single, always-current collection of types from different API schemas that you’ve added to Anypoint DataGraph and made available for consumers to query.  | 
Object types  | 
The most common type in a schema, object types represent entities in your API specification that are returned as part of a GET response.  | 
Enum types  | 
An enum type returns only a specific set of values that you’ve defined in your API specification.  | 
Union types  | 
Union types describe instances of data using other object types. A union type consists of one or more specific object types.  | 
Query types  | 
A query type is the entrypoint to an API schema when you make a request. This type contains the query methods you’ve defined in your API specification.  | 
Query methods  | 
Each unique GET endpoint defined in your API specification is represented by a query method, which you use to start a query.  | 
Fields  | 
Fields are properties you define for an object type in your API specification.  | 
Level-1 types  | 
In an API schema, Level-1 types are object types that can be directly returned by a query method.  | 
Nested types  | 
In an API schema, you can access nested types only through the query methods of Level-1 types. Nested types are not directly returned by a query method.  | 
Collaboration  | 
By enabling collaboration on Level-1 object types, you allow other types to link and merge with such types. Collaboration enables you to create a more connected unified schema so that your consumers can have a more efficient query experience. Collaboration is possible only on Level-1 object types.  | 
Linking  | 
Linking enables you to join fields from two related types that describe different objects to create a connection between them.  | 
Merging  | 
Merging types enables you to combine similar types into a single type and extend their fields and datasets for an enriched query result.  | 



