InfoPath Dev

I have a drop down in SharePoint it needs to contain about 100,000 items from an xml list. This will take too long to load. I want to make multiple small xml files dependent on the drop down above it. example drop down 1 (A-f) will pull a specific a-f.xml (drop down 2) and (g-l).xml and so on. Does anyone know of a way to point to multiple XML lists by specifying which list to pull depending on drop down. Or any better options? Right now at 10,000 items in the list it takes a while to load I'd hate to see what 100,000 items does to the list. Any help is appreciated.

 Good morning. It has been a while, but I was thinking you should be able to populate the drop-down control dynamically by querying the large XML file with LINQ.

 Online resources:

http://www.intertech.com/Blog/query-an-xml-document-using-linq-to-xml/ 

http://www.dreamincode.net/forums/topic/353127-linq-by-example-5-linq-to-xml-querying/ 

https://msdn.microsoft.com/en-us/library/bb387050.aspx

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