The Microsoft Student Champ Community had their last meeting of the year 2010, last Friday (3rd Dec). I was given the great opportunity of hosting a session as the guest speaker. It was a wonderful evening! We had a great crowd, of young university students, there. Here are the slides and SharePoint Foundation links for you to download.
http://cid-18829c69f065aa97.office.live.com/view.aspx/SharePoint%202010/SharePoint%20%202010%20Deployment.pptx
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=49c79a8a-4612-4e7d-a0b4-3bb429b46595&displaylang=en


I was trying to develop a BDC model project with visual studio 2010 and tried to change the Identifier. Once I changed the Identifier and tried to deploy. There I got an error.
In short, error will be like this
Error 1 Error occurred in deployment step 'Add Solution': Model file 'BdcModel1\BdcModel1.bdcm' has the following External Content Type activation errors:
TypeDescriptor with Name 'Identifier1' (found in Parameter with Name 'returnParameter', Method with Name 'ReadList', Entity (External Content Type) with Name 'Entity1' and Version '1.0.0.4' in Namespace 'BdcModelProject2.BdcModel1') refers to an Identifier with Name 'Identifier1' of Type 'System.Int32' which is supposed to exist on Entity with Name 'Entity1' in Namespace 'BdcModelProject2.BdcModel1'. This Identifier cannot be found.
What you have to do to solve this is very simple.
Go to Central Administration – Application Management – Manage Service Applications
There select Business Data Connectivity Services
Change the view to External Systems in the View category on the top menu bar.
Now you will see your BDC model listed there.
Just click on the model and select Delete from the dropdown menu.
In my situation I have already removed the solution from SharePoint (Retracted and Removed). If not please change all 3 views and check for your BDC model and remove it.