I haven't done work with ultra large text fields. But we basically uses a system similar to what you're describing where PHP make a querystring call to FM and parse the resulting XML output. I've worked with some pretty big result set into the several thousand records per call, but our fields are just small size of under 64 chars.
I don't see why it shouldn't work with text fields with large content since FM is just echoing the content out. I've gotten 20MB pdf files out of filemaker container fields before, the header is different, but it's basically just an echoing of a large data field just the same as if it were text.
Thank you for you answer FluffyBear, in fact it could be a solution for us, because it suposes a paradigm change from what we have planned.
Our first thought was to use Web Viewer object to call php urls, parsing data as a variables inside url, but your method is much more effective, because as far as I understand, the solution for large field contents is to make php to get data from FileMaker and once PHP gets the contents from FileMaker, transfer it out using "whatever method" instead of passing this data as a url parameters as I was planning. Actually large field contents wouldn´t be a problem because PHP (and it´s FileMaker API), should do the "echo work" for us.
I will make some trials with this point of view
Thank you for your help.
Teseo, is this a SOAP XML Web Service that you're trying to call? If so, I recommend the fm:nexus Web Services Plugin (http://fmnexus.com/products/webservices/). If you're just trying to do an XML http POST that is not SOAP, you can use the XML POST module in our free ScriptMaster plugin (http://www.360works.com/scriptmaster). If you want to set up FileMaker Server so that it is actual a server for XML Web Services requests, I recommend using our Web Services Manager products (http://www.360works.com/wsm/). Hope that helps.
Jbarnum, thank´s for your suggestion, I will take a look to those pluggins and solutions that you have propossed. Whiout doubt It could be quite interesting.