If you want your ASP.NET application to interact with a repository, SharpSVN is the preferred method.
CollabNet has a walkthrough for using SharpSVN
Content stored in SQL Server is not accessible with a version control client. You need to query the database directly, or use a framework which abstracts it & meshes with how your application is built.
Whatever you do, do not duplicate anything between SQL Server & the Subversion repository. It'll just become a massive headache.