Once upon a time, when the grass was greener and the sky was bluer, there was even an add-in application Caché RoseLink^PDF.

Here is what is in the documentation for Caché:

Disable Query Timeout — Optional. If selected, causes the ODBC client driver to ignore the value of the ODBC query timeout setting.

The ODBC query timeout setting specifies how long a client should wait for a specific operation to finish. If an operation does not finish within the specified time, it is automatically cancelled. The ODBC API provides functions to set this timeout value programmatically. Some ODBC applications, however, hard-code this value. If you are using an ODBC application that does not allow you to set the timeout value and the timeout value is too small, you can use the Disable Query Timeout option to disable timeouts.

java.sql Exceptions
The following exceptions are listed here for completeness, but are not required and are never used:
...
SQLTimeoutException
...

You can empirically verify all your considerations by calling a custom stored procedure from Microsoft SQL Server, for example:

Class dc.a [ Abstract ]
{

Query DbgSqlProc(
  qMaxRows = 10,
  qTimeWait As %SmallInt = 3) As %Query(ROWSPEC = "nrow:%Integer,name:%String") [ SqlProc ]
{
}

ClassMethod DbgSqlProcExecute(
  ByRef qHandle As %Binary,
  qMaxRows = 10,
  qTimeWait As %SmallInt = 3) As %Status
{
  #define Log(%s) Set ^dbgSqlProc(qHandle("id"),%s)=$ZDateTime($NOW(),1,1,6)
  
  Set qHandle("id")=$Increment(^dbgSqlProc)
  Set qHandle("qMaxRows")=qMaxRows
  Set qHandle("qTimeWait")=qTimeWait

  $$$Log("1_Execute")

  For i=1:1:qMaxRows Set qHandle(i)=$ListBuild(i,"name"_i)
  Set qHandle=0
  
  ; Hang qHandle("qTimeWait")*3
  
  Quit $$$OK
}

ClassMethod DbgSqlProcFetch(
  ByRef qHandle As %Binary,
  ByRef Row As %List,
  ByRef AtEnd As %Integer = 0) As %Status [ PlaceAfter = DbgSqlProcExecute ]
{
  $$$Log("2_Fetch")
  
  If qHandle>qHandle("qMaxRows") {
    Set Row=""
    Set AtEnd=1
  }else{
    Set Row=qHandle($Increment(qHandle))
    Hang qHandle("qTimeWait")
  }
  Quit $$$OK
}

ClassMethod DbgSqlProcClose(ByRef qHandle As %Binary) As %Status [ PlaceAfter = DbgSqlProcExecute ]
{
  $$$Log("3_Close")
  
  Quit $$$OK
}

}

Example of a call: select * from dc.a_DbgSqlProc(11,5)

See Customized Class Queries

Well, of course it works.
See loads data from 'C:\data\sales.csv' above.

Not quite so (see RowID Hidden?).

ALLOWIDENTITYINSERT is needed for other purposes:

• IDENTITY and Counter Values
• Copy Data into a Duplicate Table

Set Up Delegated Authentication

Have you enabled delegated authentication for services and applications, in particular for %Service_WebGateway?

Interestingly, if I try your examples, I can recreate the ambiguity error, but then get an error when attempting to specify the full param specification

What is your version of IRIS and .NET?
I have IRIS 2025.3CE and .NET 8.0/Framework 4.6.2 - the examples above work flawlessly and give respectively 1, 0, 1 as indicated in the comments.

This is also possible:

USER>s gw = $System.external.getDotNetGateway()
USER>w gw.invoke("System.Convert","ToBoolean(System.UInt64)",123)
1
USER>

Since you manage the ID yourself, in the general case it may not necessarily be a simple counter, but, for example, a Fibonacci sequence.
If the source code of the class or table is available, it is better to see how the ID is generated in it. If there is no source code, and you are sure that this is a simple counter, then in my opinion it would be easier to make a standard ID and let IRIS manage it itself.

By the way, what do you think this statement does? Note the %OpenId(20) at the end instead of %New(). 

#dim a,b,c As Sample.Person = ##class(Sample.Person).%OpenId(20)

Confusing. How about this statement?

#dim a,b,c As Sample.Company = ##class(Sample.Person).%New()​

Do you get 3 companies or 3 persons? Does it try to "cast" persons as companies? Do you get an error at compile time or run time? Would it work if Sample.Company extends Sample.Person? More confusion...

There is no confusion.

Here's another example where the class may not even exist and yet the code compiles without errors and according to the documentation.

test.MAC

#dim a,b,c As %Boolean = ##class(bla.bla).%OpenId(20)
#dim a,b,c As bla.bla.bla123 = ##class(bla.bla).%OpenId(20)

--> test.INT

Set (a,b,c)=##class(bla.bla).%OpenId(20)
Set a=##class(bla.bla).%OpenId(20),b=##class(bla.bla).%OpenId(20),c=##class(bla.bla).%OpenId(20)

The only thing is that in this case Studio Assist will not work.

A good thing to know is, that there isn't actually a thing as 'during compile time' in ObjectScript.

Do you think that the documentation contains an error?

##function
Evaluates an ObjectScript function at compile time.

#execute
Executes a line of ObjectScript at compile time.

##expression
Evaluates an ObjectScript expression at compile time.

There are nuances ;)

According to the documentation, the following two lines will give different results at the runtime:

#dim a,b,c = ##class(Sample.Person).%New() ; all the variables are assigned the same initial value
#dim a,b,c As Sample.Person = ##class(Sample.Person).%New() ; each variable is assigned a separate OREF

IRIS 2025.3.CE

ClassMethod test() [ Language = python ]
{
  import iris

  ns = iris.system.Process.NameSpace()
  try:
    iris.system.Process.SetNamespace('%SYS')

    passenger = iris.SYS.Stats.Dashboard.Sample()
    print(passenger.GloRefsPerSec)
  finally:
    iris.system.Process.SetNamespace(ns)
}

PS: Do I need a separate python iris connection for each Namespace?

• For each alphabetic character, determine its zero-based index in the lowercase alphabet (a-z).
• Preserve non-alphabetic characters unchanged.

For clarify: does alphabetical characters include only the English letters a-z, A-Z, or all Unicode characters including "ªµºÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞßàáâãäåæçèéyêëìíîïðñtóôõöøùúûüýþÿ" ?

What should be the correct result for the string "Hello World µÝ Привет Мир!" ?

Your task is to implement this encryption efficiently

What does "efficiently" mean?

The condition of the Code Golf competition has always been to write the shortest code, not the fastest (see Code Golf Index)

My current code size is 74 (where alphabetical characters only a-z,A-Z).

ClassMethod Encode(m) As %String
{
 f j=65,97{f i=0:1:25 s m=$tr(m,$c(j+i),i#2)} q $re($e(m,1,*-1))_$e(m,*)
}

"Hello World µÝ Привет Мир!" -> "риМ тевирП Ýµ 11100 01101!"

PS: why is the correct result in the testNumbers method 321 and not 213?

Caché/IRIS already has ready-made macros:
$$$FormatText(),
$$$FormatTextHTML(),
$$$FormatTextJS()

, which may be useful to you and which use #def1arg.

ISO/IEC 19075-6:2021 (see Chapter 6.4)