Migration from Caché to IRIS can be quite a challenge if your code is grown over many years
and probably not so clean structured as you may like it. So you face the need to check your
migrated code against some reference data. A few samples might not be a problem,
but some hundred GB of data for testing might be.

A possible step could be to have your fresh code in IRIS but leave your huge datastore on Caché and connect both environments over ECP. I have created a demo project that gives you the opportunity to try this based on 2 Docker images with IRIS and with Caché connected over ECP.

As you know ObjectScript has neither FOREACH system command nor system function.
But it has a wide room for creativity.

The task is to loop over a global or local array and do something FOR EACH element.

There are 2 possible solutions:

This is a demo to make use of a simple WebSocket Client with Embedded Python in IRIS.

How to Test it

• Run an Iris Session in Docker
• Select your WebSocket Echo Server
• Enter the text you want to send or generate it
• Send it and see the result

$ docker-compose exec iris iris session iris "##class(rccpy.WSockPy).Run()"

*** Welcome to WebSocket Embedded Python Demo ***

Every now and then you may encounter a situation where for various reasons
ODBC is the only option to access a remote system. Which is sufficient as long as you need to examine or change tables.
But you can't directly execute some commands or change some Global.

The demo is based on the raw class descriptions.
The data classes used are Address, Person, Employee, Company
For a more attractive demo, a JSONtoString method by ID was added.

Caused by a conflict in the port assignment I get this entry in mesages.log and SMP doesn't respond:

In most cases, a global used by default storage has just 1 subscript level that represents the IDKEY.
For an index-globals we may see 2 or more subscript levels.
Arrays, or parent-child relationships or persistent classes extending a base data class
are examples where we see more levels. Though all these globals are quite uniform.

Standard error logs in IRIS / Caché / Ensemble are written global ^ERRORS.
As this piece dates back some decades back to previous millennium its structure
is far from the typical SQL storage structures.

where can I find a list of all command line utilities with a short description?