I’m not quite familiar with the .asmx webservice. Is that by any chance related to Visual Studio? If so, it’s been a few years since I’ve worked with Visual Studio, and I’m not sure how the program currently is set up. I probably wouldn’t be much help in that area.
If you’re able to access your database online, then you absolutely should be able to use a web component in AppyBuilder to help you out.
I found some older documentation from the AI2 platform regarding XML & Web Services.
This example looks like it’s taking a website and decoding the XML from the website.
So it’s similar to what we did in my example, except it’s using XML instead of JSON
I hope that helps, if not, let me know, I’ll see what else I can do to help