Summary

• Metadata is data that describes other data. It is important in applications that need the ability to identify and possibly adjust to changes in the backend data store.

• In ADO.NET, metadata is exposed through the DbConnection object's GetSchema method, which you can call with no parameters to get a metadata collection list.

• The GetSchema method contains an overload that accepts a collection name, such as Tables or Databases.

• You can use a GetSchema overload that accepts a collection name and an array of restriction filter strings to narrow the scope of the returned data.

• The metadata can be changed to get the behavior that you desire, or extended to add more metadata options.

• The unique identifier parts are the restrictions you are required to pass to the GetSchema method to retrieve a single unique value.