Updating or Deleting an Item in a Public and Custom Folders

Unlike reading from or inserting into a Public or Custom folder, you do not need the FolderId in order to update or delete an item. You simply need to know what type of object the folder contains and use that type as the Table (or use Inbox for a folder that contains Messages). For example:

Updating a Message item in a custom folder:

UPDATE Inbox SET Subject = 'Updated email message' WHERE ItemID = 'AZQ111222...')

Deleting a Contact item from a Public Folder:

DELETE FROM Contacts WHERE ItemID = 'AZQ111222...')