Thanks user357034 for getting me here (I'd "up" your answer but I'm new and don't have any reputation). I wanted to post the code I used in case others run into this. And also get any feedback if you see anything that looks goofy here.
First, I created an ASP file like so
Dim orderid
Dim status
orderid = Request.QueryString("orderid")
status = Request.QueryString("status")
sql = " update Orders " & _
" set OrderStatus = '" + status + "' " & _
" where Orderid in (" + orderid + ") " ;
set fs=Server.CreateObject("Scripting.FileSystemObject")
set f=fs.OpenTextFile(Server.MapPath("./MY_FILE.sql"),2,true)
f.WriteLine(sql)
f.Close
set f=Nothing
set fs=Nothing
I FTPed that up to the "generic" folder on Volusion.
Next, in PHP, I call this file, similar to this...
$asp = file("http://MY_SITE/v/vspfiles/schema/generic/MY_FILE.asp?
orderid=11,12&status=Processing");
foreach ( $asp as $line )
{
echo ($line);
}
NOTE: I already FTPed an XSD file to the same folder with the same name, like MY_FILE.xsd.
And finally, I make a web service call to my service, like this...
$url = "http://MY_SITE/net/WebService.aspx?
Login=XXXX&EncryptedPassword=YYYYY&API_Name=Generic\MY_FILE"
Works great. I go into the Volusion admin site, look at the Orders 11 and 12, and they were updated. I'm using this method for several areas in Volusion where their API is lacking. Thanks!