The metadata services introduce a new dimension of customization that goes beyond basic data manipulation. It opens new doors for user-interface customizations as well as generic processing where the schema of the entities you are dealing with is unknown until runtime.

On top of the two queries we described in this recipe, you can query specific-attribute details, relationships, global option sets, and much more.

For further details, visit the following MSDN article at https://msdn.microsoft.com/en-us/library/mt607522.aspx.