Android: GUID Primary key

Question

I know if I don't use a field named _id as my primary key in Android, that certain things like the CursorAdapter won't work, but does the _id column need to be an autoincrement int?

Could I use a Guid as the key, as long as it's called _id, and have the CursorAdapter still work?

Answer 1

The yellow box in the storage guide says:

Android does not impose any limitations beyond the standard SQLite concepts. We do recommend including an autoincrement value key field that can be used as a unique ID to quickly find a record. This is not required for private data, but if you implement a content provider, you must include a unique ID using the BaseColumns._ID constant.

Now when you click on the BaseColumns class you will see

public static final String _ID

The unique ID for a row.

Type: INTEGER (long)

Constant Value: "_id"

So I guess, a GUID will not work.