Is the best way really to index this to a database and how?

Hi!

I need some good tips from you here guys because it sound like my plan fails.

I have a site where I index XML documents (about 10) with products. Each XML document has about 10 000 rows and my first thought was to index it into an MySQL database because it is from different suppliers who has named the nodes in the xml documents differently and I will give my user the ability to filtrate there search result by for example price < $100.

Theirs XML documents will also be updated very frequently (every 10 minute) and they just have one pubDate I can compare with and it is for the whole document.

So how should I do this?
Should I index it to an database table?
- It sounds stupid to delete all data in my mysql table to add all new data every 10 min but I want to show my visitors fresh data.
- Is it possible to compare my data in my database to see whats gone in the new xml file and whats deleted? And just insert the new data and delete the data that doesn't exists in the new XML document?

OR

Should I NOT index any data into a database table and try to get out the correct information from their xml file every time?
- I have understand that it is really difficult to make for example this statement in xml document price < $100. And remember that I will index this from different suppliers, so one supplier could have named it price and another sellprice.

To be honest I doesn't think any of these ideas are really good so please help me. What is the best way to solve this in my position?
I want my visitors to always have fresh data and be able to filter there search results by price, name ...

To help you more so is it last minute travels that I want to index.
And here is two different xml sources, please check them out and try to help me.
stsalpresor.se/feeds/lastminutefeed_alpresor.xml
fritidsresor.se/Blandade-Sidor/feeds/tradedoubler/

 

Can I donfirm my understanding of your problem?

You have a SQL Database that is regularly updated, and you want your feeds to be updated with this new data every 10 minutes?

Am I right?