There isn't a hard limit on the number of tasks, but you may run into licensing issues. As you set them up, you choose the user they run as, so if that user has too many connections going at once, or if they're run as more different users than you have licenses for, there could be an issue.

Once you know the pid, try:

set process = ##class(%SYS.ProcessQuery).%OpenId(pid)

Then check process.Routine, or process.CurrentLineAndRoutine.

Here's how I've been doing this:

//Read in content from the HttpRequest
set req = %request.Content.Read()

//Convert content from JSON to a dynamic object
set reqObj = {}.%FromJSON(req)

//Access data from within the new dynamic object
set userName = reqObj.%Get("UserName")

Why not do this?

set rset1 = ##class(%ResultSet).%New() 
set query = "Select statment" 
set sc = rset1.Prepare(query) 
set:+sc sc = rset1.Execute(parm1, parm2) 
set ^sql = query

Have you checked the security settings for the user you're logging in as? You should have %Developer and %DB_USER, I think. Or if you have %All, that works too.

This is a long shot, but is the ODBC connection defined in User DSN or System DSN? We had an issue after a recent round of Windows updates where Excel suddenly wasn't always correctly seeing the System DSN connection, and setting it up under User DSN instead resolved that issue.

Here is some useful documentation.

You're going to want to make a class that extends %CSP.REST and set up an application that uses that class as its dispatch class. You'll have a URL map in that class to tell IRIS or Cache what to do with the request. Depending on your specific application, you might also want to get familiar with using %request and %response in that process.

If you're using the IRIS ODBC driver, try switching to the IRIS ODBC35 driver. This kind of error may mean that the application is expecting the driver to do some ODBC 3.x stuff that the older driver might not be capable of.

The ones in italics are the ones that are a part of your current project. If you click on the Project tab, they'll show up there too.

..Adapter.SSLConfig should get you the name of the SSL Configuration that the adapter is using. The property of the %Net.HttpRequest is called SSLConfiguration. So it should be:

set httpRequest.SSLConfiguration = ..Adapter.SSLConfig