When I create a list in SharePoint and want to run LINQ agaisnt it I use SPMetal to auto generate the mapping.
SPMetal.exe /web:http://mysite /code:C:\MyFile.cs
This does not seem to generate the bindings for extenal lists. How could I generate the bindings?
Would I be better off not using LINQ and using the SharePoint Object Model ( http://www.zimmergren.net/archive/2010/01/19/sp-2010-programmatically-work-with-external-lists-bcs-in-sharepoint-2010.aspx )
LINQ to SharePoint spmetal.exe does not support external lists http://nileshmandekar.blogspot.com/2011/04/limitations-of-external-list-using-bcs.html
But there is an article how to make it work: http://fabiangwilliams.wordpress.com/2010/01/03/how-to-using-spmetal-utility-in-sharepoint-2010-to-presumably-manipulate-data-on-a-bcs-external-list/
I suggest to use SharePoint Object Model as a more tested & recommended API for working with External Lists
If the objective is just to query lists using LINQ and you can directly do that without SPMetal. LINQ can be directly used on SPListItemCollection e.g.
SPlist CustomerList = Web.TryGetList("Customers");
var FindCustomer = from SPListItem Item in CustomersList.Items
where Item["Orders"] as int == 5
select Item;
//or select new{Title = Item["Title"]}
This does not have hard coded entities but is more flexible. And as long as your list column names remain same, code can be deployed on any environment without recompiling (even if other lists are changed). Also you can choose to retrieve few chosen field's data instead of retrieving data of all the fields every time.
