| 摘要 |
A method for extracting metadata for plural related objects of different types from a database includes defining a heterogeneous object type as a collection of database objects of different types. Upon a request to fetch a particular heterogeneous object, member objects of the heterogeneous object are fetched from the particular heterogeneous object in a specific order based on the definition of the heterogeneous object's type, such as a valid order for re-creating the particular heterogeneous object. The set of member objects to be fetched can be restricted according to at least one specified filter, which itself may be translated into a second filter according to a type of a member object being fetched. Such translated filters can inherit values from the filter specified in the request for the particular heterogeneous object type, or can have a fixed value of some data type. The extracted metadata can be formatted to recreate the particular heterogeneous object. |
