Why can't you insert-select into the normalized tables, in order of dependency, to get the data moved over. 15m rows is not a very large amount so I assume the storage would not be a big issue. That should be simple to implement and reasonably quick to perform.

This is hard to answer because we don't know why you need to do this and we can't think of a good reason on our own. I will say that using cursors is most certainly not a good idea. I assume the SProcs work on a single record at a time as well.

1. What is the problem driving the requirement? Performance, storage, regulatory?

2. Are you still receiving new transactions or is this intended to archive the data?