最佳实践 - 使用rails应用程序中的重要验证逻辑将XML解析为数据库

I'm receiving big (around 120MB each), nested xml files. The parsing itself is very fast, currently i'm using the Nokogiri:SAXParser which is way faster then a DOM based. I need to check back a lot of values in the database. (Should it be updated or not?) Also i keep database queries as low as possible (eager loading, pure sql selects) the performance loss is about 40x in comparision to parsing only. I can't use mass inserts due to the need of validation/check back existing records/a lot of association involved. The whole process is in a transaction which speeded up things around 1.5x . What approach would you take? I'm looking forward to any help! I'm not very skilled in the whole XML thing. Would XLST help me? Also i have a XSD file for the files which arrive me.I'm receiving big (around 120MB each), nested x