Most version control tools operate on the local disk file system.
Database objects for most relational database systems
Do you necessarily need to track EVERY change made to an object or just the last one? We wrote a solution in C# which works against TFS in that we have a baseline of all the SQL objects in the database and then using the methods from Microsoft.SqlServer.Management.Smo we just go thru each database object and compare the 'working set' to the server version. We run it at night as part of our evening processing and it takes about 15 minutes to go thru the entire server of 9 databases. We've found that it works great, doesn't involve any direct modification to SQL servers/databases and it works for SQL 2005/2008. It generates a report that gets mailed out to our database admin letting them know what objects have changed, then allows them to go thru TFS and see whats what.
I had originally started here; http://odetocode.com/blogs/scott/archive/2008/02/02/versioning-databases-change-scripts.aspx
but found that what I was looking for wasn't so much a way to push changes to a server but to simply know the changes. The blog link has a few decent suggestions, might be helpful hopefully.
regards.