I have a problem similar to the one in this post
with a blog that has over 10,000 entries (www.comicsbeat.com). My developer imported all the posts from the old site by hand because the old database was modified. I think about 95% of the site was imported but there were some that did not get included because of duplicate post IDs.
However, rather than re-import them all as in the above post, I would like to simply find the duplicate posts and reimport them separately. I'm guessing there is a way to compare databases. Any ideas on how to do this?