You can add property to the task class which references this table.

Would it help?

Please elaborate on what do you want to do with ID.

What do you want to achieve?

Awesome work!

What's the error with

SELECT * FROM DUAL;

and W methods?

Some good ideas.

If you're unable to receive data at ll, start with a simple query and check if it works:

SELECT * FROM DUAL;

I never use hardcoded global names in code, all global references are defied as macros (preferable) or parameters (allows overloads).

Readme or documentation can provide some additional information on used globals but more as a reference.

Try it like this:

/// d ##class(isc.test.Utils).Test2()
ClassMethod Test2()
{
    set from = "^A"
    set to = "^B"
    kill @from, @to
    set @from@(1) = "A"
    set @from@(2) = "B"
    set @from@(3) = "C"
    
    do ..InvertList(from, to)
    
    zwrite @from,@to
}

ClassMethod InvertList(from, to) As %Status
{
    #define ForAll(%in,%gn) s gn%in=$na(%gn) s %in="" f { s %in=$o(@gn%in@(%in)) q:%in=""
    #define EndFor }

    $$$ForAll(key, @from)
        set @to@(@from@(key))=key
    $$$EndFor
}

For me it returns

^A(1)="A"
^A(2)="B"
^A(3)="C"
^B("A")=1
^B("B")=2
^B("C")=3

"For Each" for a global?

This is For each for a global, not local variable.

Use BindParameters / SetParameter to set parameters instead of concatinating.

Enjoy.

#define ForAll(%in,%gn) s gn%in=$na(%gn) s %in="" f { s %in=$o(@gn%in@(%in)) q:%in=""
#define EndFor  }

set glvn = "^MyGlobal"
$$$ForAll(value, @glvn)
    write value,!
$$$EndFor

Metrics can store history, i.e.:

Property MetricProperty As Ens.DataType.Metric (AUTOHISTORY=50) [MultiDimensional];

Docs.

Check @Alexey Maslov answer - it is a correct solution for your use case.

Still, to set environment variables for current you can use this utility.

Extend %Fileman class:

Class MyFilemanDate Extends %FilemanDate {

Parameter STRICTDATA = 1;

}

And call it:

##class(MyFilemanDate).LogicalToDate()