The title of the contest subject is not quite precise but addresses the %Library.classes involved.
What is meant is officially named Class Query and is dating back to the early days of Caché.
CLASS is used because it is embedded in a COS class.
Though there is a precise description in the official documentation it remains rather abstract.
My tutorial should guide you step-by-step through a simple example in COS to make it tangible to you

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Data analytics is a crucial aspect of business decision-making in today's fast-paced world. Organizations rely heavily on data analysis to make informed decisions and stay ahead of the competition. In this article, we will explore how data analytics can be performed using Pandas and Intersystems Embedded Python. We will discuss the basics of Pandas, the benefits of using Intersystems Embedded Python, and how they can be used together to perform efficient data analytics.

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One of the reasons why I love Cache and Iris is that not only you can do anything you can imagine, also you can do it in a lot of different ways!!.

Imagine that you have an integration running with IRIS connected by ODBC you probably only run SQL queries but you can also create stored procedures and inside write the code to do everything you can imagine.

I'm going to give you some examples but the limit is your imagination!!

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Make sure you have git installed.

I created a git folder inside the IRIS mgr directory. I right clicked the git folder and chose Git Bash Here from the context menu.

git clone

Clone my csp-log-tutorial GitHub repo if you like to try it out for yourself.

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I have experienced that my iris server is gone due to upgrading the docker version when I have built IRIS server on docker container.

Based on this experience, I'd like to show you how to make a backup for the IRIS server before upgrading platform or docker, and the procedure for rebuilding the IRIS in a new environment.

IRIS server backup procedure

When you have finished building for the IRIS server, you need to make a backup.

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Iryna Mykhailova · Mar 16 6m read
Kinds of properties in IRIS

InterSystems IRIS has quite a few different kinds properties. Let’s put them in order so that they make better sense.

First of all, I would divide them into categories:

  • Atomic or simple properties (all those %String, %Integer, %Data and other system or user datatypes)
  • References to stored objects
  • Built-in objects
  • Streams (both binary and character)
  • Collections (which are divided into arrays and lists)
  • Relationships (one-many and parent-children)

Some of these kinds of properties are quite straightforward. For example, atomic properties:

Property Name As %Name;
Property DoB As %Date
Property Age As %Integer

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In some of the last few articles I've talked about types between IRIS and Python, and it is clear that it's not that easy to access objects from one side at another.

Fortunately, work has already been done to create SQLAlchemy-iris (follow the link to see it on Open Exchange), which makes everything much easier for Python to access IRIS' objects, and I'm going to show the starters for that.

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Hi all!

In this article I would like to review those VS Code extensions which I use myself to work with InterSystems and which make my work much more convenient. I am sure this article will be useful for those who are just starting their journey to learn InterSystems technologies. However, I also hope that this article could be useful for experienced developers with many years of experience and open up new possibilities for them when using VS Code for development.

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This article is intended to be a simple tutorial on how to create ODBC connections and working with them, since I found starting with them a little bit confused, but I had amazing people to take my hand and walk me through it, and I think everyone deserves that kind of help too.
I'm going to divide each little part in sections, so feel free to jump to the one you feel the need to, although I recommend reading everything.

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InterSystems IRIS versions 2022.2 and newer feature the ability to authenticate to a REST API using JSON web tokens (JWTs). This feature enhances security by limiting where and how often passwords transfer over the network in addition to setting an expiration time on access.

The goal of this article is to serve as a tutorial on how to implement a mock REST API using InterSystems IRIS and lock access to it behind JWTs.

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I've been working for some days in the connectivity between NodeJS client applications and IRIS as server using web sockets.

You can get all the information in relation to the web socket connections using IRIS as a client or as a server from this URL:

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Robert Cemper · Mar 2 4m read
Tutorial - Streams in Pieces

This tutorial is a follow on to Working with %Query
It was displaying the content of the input stream chopped in fixed-size chunks.
But often those streams are structured and have well-defined separators (e.g HL7)
So as a side subject of this tutorial, this chapter shows how to break a stream into PIECES.

It is exactly the same idea as the $PIECE() function for strings with some add-ons.

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My previous article introduced you to SQL based Basic Class Query
where a clever wizard created all the required code for you and your essential
contribution was an SQL statement.

Now we enter the real Custom Class Query that provides more freedom but
requires a deeper understanding of the mechanic behind the scene.
The full code example is again on GitHub

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This is a simple tutorial on the quickest way I found to create a sample database for any purposes such as testing, making samples for tutorials, etc.

Creating a namespace

  1. Open the terminal
  2. Write the command "D $SYSTEM.SQL.Shell()"
  3. Write "CREATE DATABASE " and the name you want for your namespace.

Now you have a new namespace in a faster way than creating it from the Management Portal - which of course offers way more configuration options.

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For some years I missed being able to offer, to everybody interested in ObjectScript, a tutorial more or less complete, to start with ObjectScript. Something that could help more and make things easier to those new developers that come to our technology... something intermediate, halfway between the common "Hello World!", that doesn't really get you further, and the "Advanced Training", that is unaffordable because of lack of time,etc.

If there were something truly helpful not only as an introduction to the ecosystem, but as a starting point, as a boost, to really start to walk into ObjectScript and move forward by yourself... wouldn't that be awesome?

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or "So you just got yelled at by your boss, for sending him an unformatted Hello World webpage"

Our previous lesson ended with us serving a Message value obtained from a Caché REST service to the client, using Angular as a runtime. While there is a lot of moving parts involved in this process, the page is not especially exciting at the moment. Before we can start adding new features, we should take a step back and review our tools.

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Pouring The Coffee: Creating and scheduling a task

Don't you wish a fresh, hot cup of coffee could be waiting for you right when you get into the office? Let's automate that!

Cache and IRIS come with a built-in Task Manager, which should have a familiar feel to those used to using the Windows task scheduler or using cron on Linux. Your user account will need access to the %Admin_Task resource to use it, and you can access it in the management portal under System Operation -> Task Manager. When first installed, there are roughly 20 types of task that you can schedule.

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I wrote a step by step tutorial in the qewd-howtos repository how you can write state of the art multi-page web apps with Node.js using a QEWD-Up WebSocket/REST api back-end integrated with a mainstream web framework like NuxtJS & Vue.js.

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Hi Developers!

Many of you publish your InterSystems ObjectScript libraries on Open Exchange and Github.

But what do you do to ease the usage and collaboration to your project for developers?

In this article, I want to introduce the way how to introduce an easy way to launch and contribute to any ObjectScript project just by copying a standard set of files to your repository.

Let's go!

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Lily Taub · Mar 19, 2019 9m read
A Tutorial On WebSockets


Most server-client communication on the web is based on a request and response structure. The client sends a request to the server and the server responds to this request. The WebSocket protocol provides a two-way channel of communication between a server and client, allowing servers to send messages to clients without first receiving a request. For more information on the WebSocket protocol and its implementation in InterSystems IRIS, see the links below.

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How can you allow computers to trust one another in your absence while maintaining security and privacy?

“A Dry Martini”, he said. “One. In a deep champagne goblet.”
“Oui, monsieur.”
“Just a moment. Three measures of Gordons, one of vodka, half a measure of Kina Lillet. Shake it very well until it’s ice-cold, then add a large thin slice of lemon peel. Got it?”
"Certainly, monsieur." The barman seemed pleased with the idea.
Casino Royale, Ian Fleming, 1953

OAuth helps to separate services with user credentials from “working” databases, both physically and geographically. It thereby strengthens the protection of identification data and, if necessary, helps you comply with the requirements of countries' data protection laws.

With OAuth, you can provide the user with the ability to work safely from multiple devices at once, while "exposing" personal data to various services and applications as little as possible. You can also avoid taking on "excess" data about users of your services (i.e. you can process data in a depersonalized form).

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Hi Developers!

Recently we launched InterSystems Package Manager - ZPM. And one of the intentions of the ZPM is to let you package your solution and submit into the ZPM registry to make its deployment as simple as "install your-package" command.

To do that you need to introduce module.xml file into your repository which describes what is your InterSystems IRIS package consists of.

This article describes different parts of module.xml and will help you to craft your own.

I will start from samples-objectscript package, which installs into IRIS the Sample ObjectScript application and could be installed with:

zpm: USER>install samples-objectscript

It is probably the simplest package ever and here is the module.xml which describes the package:

<?xml version="1.0" encoding="UTF-8"?>
<Export generator="Cache" version="25">
  <Document name="samples-objectscript.ZPM">
      <Resource Name="ObjectScript.PKG"/>

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Hi Developers!

This post describes how you could publish your InterSystems application on Open Exchange.

What is the InterSystems application?

It could be anything, which is built with InterSystems data platforms or to help work with InterSystems data platforms: InterSystems IRIS, InterSystems IRIS for Health, InterSystems HealthShare, InterSystems Ensemble and InterSystems Caché. This could be tools, frameworks, adapters, examples and business solutions.

Why publish on Open Exchange?

InterSystems Open Exchange is an "App Central" for the solutions in InterSystems. It's the first place where the developer goes to look for tools, frameworks, and examples on InterSystems IRIS. And Open Exchange brings the added traffic to your solution which could be converted into leads.

We are having a set of business development tools for published Open Exchange applications. This definitely makes your InterSystems application more noticed.

Submitting an application

Suppose you have a library with open source published on Github which you want to publish on Open Exchange. For the purpose of a demo, I'll fork this remarkable project of @Peter Steiwer ObjectScript-Math which I forked and renamed to object script-super-math.

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