I have a DataTable obtained from a SQL DataBase, like this:
using (SqlCommand cmd = new SqlCommand(query, _sqlserverDB)) { using (SqlDataAdapter adapter
As David says ... you are in .NET so the types will be .NET types. This is a listing of type mappings from SQL Server to .Net that shows you what .NET type you will end up with for a given Sql column type .. hope this helps ..
http://msdn.microsoft.com/en-us/library/ms131092.aspx