My Sharepoint Learnings

Sometimes even as the administrator, the error " Access Denied by Business Data Connectivity" might come when trying to open external list To resolve the issue Go to Central Administration -> Application Management -> Manage Service Applications -> Business Data Connectivity Service* -> [Your Entity] -> Set Permissions Then set the permissions as re quired  Then do an IISReset    

External lists in Sharepoint 2010 can be used to read/add/update/delete data in any external data- source. To create external list, a external content type has to be created. Refer the below links on msdn on how to create external content type How to create external content type Creating SharePoint Server 2010 External Content Type Associations with SharePoint Designer 2010 Sharepoint-2010-external-content-type-to-read-data-from-sql-server-using-sql-authentication-and-secure-store-service.aspx The below links explain on how to create external list How to create external list https://www.nothingbutsharepoint.com/sites/eusp/Pages/sharepoint-2010-external-lists.aspx More about BCS functionality in msdn http://msdn.microsoft.com/en-us/library/ee557949.aspx