User Answers

Security.System is a persistent class with 1 object in it. The ID of the object is "SYSTEM". So this works

set ss = ##class(Security.System).%OpenId("SYSTEM")
write ss.AutheEnabled

The approach above is best if you want to access several properties. But if all you really want is one or two properties of Security.System, you can do this:

write ##class(Security.System).AutheEnabledGetStored("SYSTEM")

You are correct. EventData is the field to use. Here's an example  query (run from %SYS namespace):

SELECT UTCTimeStamp, EventSource, EventType, Event, EventData, Username, Description
WHERE (UTCTimeStamp BETWEEN '2018-10-27 00:00:00' and '2018-10-27 23:59:59') AND (EventData = '12345') AND (Namespace = 'ABC')
ORDER BY UTCTimeStamp DESC, SystemID DESC, AuditIndex DESC

I think you are asking: "If I have an object open in one process, and another process updates that object or its corresponding row, what's the best way for the first process to make sure that it has the latest version of the data?"

I recommend using %Reload(). It makes it clearer to another developer what you're actually doing. A quick glance at the %Reload() code makes me think that it would be faster than killing the object and calling %OpenId() to reopen it.

It is possible to programmatically add a relationship to two persistent class definitions at runtime, and then compile those classes. That gives you the same result you'd get if you had added the relationship to the class definitions at design time. So I don't think that's what you want.

Here is some information about debugging CSP pages using Studio. I actually just taught this to students in class yesterday!

1. You can't set a breakpoint inside the ObjectScript on a CSP page (inside a <script> tag). But the workaround for this is to use the View > View Other Code and load the class definition that's generated from the CSP page. Then you can set breakpoints normally.