An alternative to using the SQL version of the data dump is to use the XML as provided directly in the data dump. Most platforms provide a streaming XML reader: all you've got to do is load
posts.xml (IIRC - I don't have a dump handy), load it in a streaming manner and write out all the posts with the relevant owner ID to whatever file format you want. If you just want to write out the XML for the posts you own, you can just hold open a streaming XML writer and write the element - easy!
Depending on what you've got in terms of database connectivity etc, that may well be easier to do. Let me know if you want some C# code to do this.