What's the best way to redirect 1,000,000 unique URLs to another 1,000,000 unique URLs?
These pages are all combinations of multiple search filters and queries. We're migrating the site to cleaner URLs and want to map old pages to new ones so that we do not lose visitors or send them to 404s.
I believe a million line .htaccess will slow down the site pretty significantly. Is there a better way that would maintain PageRank but not slow down the site? Maybe something I could put on each page individually?