1840-12-31 00:00:00 is point Zero of internal time setting.
It applies as default to empty data type Ens.DataType.UTC

embedded SQL is probably an overkill for this formating.
Just convert it to the internal format, add what you need and assemble the pieces in COS

if you know exactly what characters you want to remove you may use $TRANSLATE (in SQL) !

docs: https://cedocs.intersystems.com/latest/csp/docbook/Doc.View.cls?KEY=RSQL_d_translate

for the fixed part you still can use classic mapping.
for the variable section you may set  CONTENT = "MIXED"  for the containing property
and get the raw XML structure in hands .
You can then analyze this "inner" XML using class %XML.TestReader

The example  and the class are simply wrong 
A %Library.DynamicObject that is composed here just has neither a method  %Clone nor a method %Compose

You may report the bug to WRC

DCOUNT is a function of MV Basic. Not of ObjectScript !

should do the trick 

take a look at %Library.Persistent. Methods

• %Open, %OpenId have a 3rd call parameter status  that returns a %Status value indicating success or failure.
• %Delete, %DeleteId do it as direct result  by a %Status value indicating success or failure.

No further need of an %On.... to know success or failure 

Allmost!  3rd Update

since if the left side is a Unix Timestamp, then you get this result:

docs: https://docs.intersystems.com/iris20201/csp/docbook/Doc.View.cls?KEY=RCOS_fzdatetime 

timezone conversion from UTC may compensate  the 6 hours difference ! 
 in Middle Europ we have we have 2 hrs+  to UTC so

 method OpenSFTP(ByRef sftp As %Net.SSH.SFTP) as %Status

Open up an SFTP session for SFTP activity.

 ByRef this means that the variable you pass has to be initialized first.

 just binds the object type to variable  sftp but doesn't initialize it.
So it is <UNDEFINED>

Use your  original line instead or in addition to initalize it

I had to transfer more than a few files. so I shared a docker  volume:

docker run  ...... --name=iris1 -d -v volume1:/external   ........
docker run ....... --name=iris2 -d -v volume1:/external   ........

so both containers  have permanent access and can pass files as we use to pass Globals using IRISTEMP  or CACHETEMP

The volume gets generated at first access automatically

see: https://cedocs.intersystems.com/latest/csp/docbook/Doc.View.cls?KEY=RSQL_into 

&sql(SELECT Name, DOB, Gender INTO :Name,:DOB,:Gender
      FROM osuwmc_RQGPatient.DataTable WHERE MRN=:MRN)

I think not that this is possible.
The reason was to make it as flexible as any other Dynamic query.
I'm convinced this was necessary to support Sharding.

But you have the option to write your own custom class query 

I'd like to say a bigThank You ! to all participants that gave me their vote.

And I forgive the unknow experts that voted for me in the beginning and changed their mind shortly before closing as by the rules.

You did a very interesting presentation of the essential concept of Globals that was developed once by Neal Pappalardo in 1966/67. 
Long before objects were even thought of.
So back to the roots !
( Neil Pappalardo is the founder and CEO of MEDITECH )

You need to start with require("cache")  to have the basic access module.

you find it a cache.node   for various rather old versino0n of Node.

it is in %instaldir%\bin\ 

more details in   %instaldir%\ \dev\node.js\samples\installed_software.js

 and more ......

¡ Hola Salva ! ( @Jose Tomas Salvador)  

You motivated me to give it a try.
And  with a little bit of tweaking the scripts my contribution for the contest 
WebSocket Client JS with IRIS Native API as Docker Micro Server  
is also running with no issues on Docker Desktop for Windows !
A very positive experience that I didn't expect at first sight.
¡ Gracias !

if you install Excel you have automatically also a DSN for ODBC access to EXCEL
check your DSN data sources in your Windows installation.
Use ODBC-Gateway in Cache / IRIS to access it.