I have been after a link to a web page that gives a mapping of ADO to SQL Server data types. The best I have found is currently, Writing Secure Code : Chapter 12: Securing Web-Based Services, Table 12-1 A Data Type Rosetta Stone.
Edit 1: I have also found An ADO Command Factory for Stored Procedures : Table 1. SQL Server and Access data types which shows SQL Server 7 and ADO data type mappings.
Edit 2: Many thanks to John Barone who posted a comment providing a link that pointed to the table I used to use as a definitive guide to ADO/Database data type mappings, Carl Prothman.NET : Data Type Mapping.
If anyone has any better links please let me know!