Robert Cemper · Nov 11, 2017 3m read
Summary on Local Variable Scoping

This should be an overview over a subject that pops up over several places in online documentation mostly as remarks and never as dedicated chapter.

Once upon a time ... No it's not a fairy tale.
In the beginning of Caché (and before) you had your partition to run your code. Part of that partition was a space with all your local variables nicely sorted by %,A,..Z,a,...z

14 3
1 779
Robert Cemper · Feb 8, 2019 2m read
Client for WebSockets based on Node.js

WebSockets as a communication technology wins increasing importance.
In the SAMPLES namespace, you find a nice example for running a WebSocket Server.
There is also a useful example for a Browser Client. JavaScript does most of the work.

My point is:
How to consume the output of a WebSocket Server in your application?

14 2
1 707

As you know in Caché / IRIS you have the possibility to define a property as Multidimensional as documented here:
and the explanation of how to use it

Though the access is quite comfortable (in traditional COS sense) there are 2 main restrictions that hurt:

#1) It is not saved to disk unless your application includes code to save it specifically.
#2) It cannot be stored in or exposed through SQL tables
there are some more
I'll show how to overcome these limits

14 0
2 365

"Telegram" is a well-known instant messenger, which provides an API for creating bots. The features of this API allow you to create bots with a wide range of functionality including receiving payments.
With the help of the telegram bot, I solved a simple task - sending Alerts from Ensemble to Telegram.

Advantages: Alerts come to the mobile phone, a notification appears, so there is no need to install any additional applications (in contrast to the solution httpoutboundadapter).

The bot can be extended by adding new commands, for example, for managing the Production or for solving other tasks in Iris, Ensemble or Cache.

14 0
6 1,117
Robert Cemper · Jun 25, 2020 12m read
Backport %JSON.* to Caché


This is a coding example working on Caché 2018.1.3
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

Full backport from IRIS for Windows (x86-64) 2020.1 (Build 215U) Mon Mar 30 2020 20:14:33 EDT

IRIS brought us an excellent %JSON.Package
It is an essential component of the Project Manager (ZPM)
This backport makes it available also in Caché and builds a base to eventually backport also ZPM.

14 5
0 347


This is a list of all the posts in the Data Platforms’ capacity planning and performance series in order. Also a general list of my other posts. I will update as new posts in the series are added.

You will notice that I wrote some posts before IRIS was released and refer to Caché. I will revisit the posts over time, but in the meantime, Generally, the advice for configuration is the same for Caché and IRIS. Some command names may have changed; the most obvious example is that anywhere you see the ^pButtons command, you can replace it with ^SystemPerformance.

While some posts are updated to preserve links, others will be marked as strikethrough to indicate that the post is legacy. Generally, I will say, "See: some other post" if it is appropriate.

Capacity Planning and Performance Series

Generally, posts build on previous ones, but you can also just dive into subjects that look interesting.

14 0
5 5,119
Robert Cemper · Feb 16, 2018 4m read
The adopted Bitmap

No doubt bitmap indexing, if used with a suitable property, performs just impressive!
But there is a major limit: ID key has to be a positive integer.
For modern class definitions working with CacheStorage this is a default.

BUT: There are hundreds (thousands ?) old applications out in the field that
are still using composite ID keys.
Or - to name the origin - work on Globals with 2 subscript levels (or more).
They are by construction excluded from our "Bitmap Wonderland".

14 1
1 757

The Amazon Web Services (AWS) Cloud provides a broad set of infrastructure services, such as compute resources, storage options, and networking that are delivered as a utility: on-demand, available in seconds, with pay-as-you-go pricing. New services can be provisioned quickly, without upfront capital expense. This allows enterprises, start-ups, small and medium-sized businesses, and customers in the public sector to access the building blocks they need to respond quickly to changing business requirements.

Updated: 10-Jan, 2023

14 2
6 4,554

This week I am going to look at CPU, one of the primary hardware food groups :) A customer asked me to advise on the following scenario; Their production servers are approaching end of life and its time for a hardware refresh. They are also thinking of consolidating servers by virtualising and want to right-size capacity either bare-metal or virtualized. Today we will look at CPU, in later posts I will explain the approach for right-sizing other key food groups - memory and IO.

So the questions are:

14 10
2 4,332

The question has come up several times and I saw mixed answers and no quick example

My personal preference is using CPIPE device as you get back exactly the output you will get at the command line interface of your OS .
The tricky thing is to stop reading in time.
The example just displays what you normally see in your console.
it becomes useful if you look for things that you can't get from any $system.whatever()

14 5
3 1,589
Timothy Leavitt · Jul 8, 2020 7m read
Tips for debugging with %Status


If you're solving complex problems in ObjectScript, you probably have a lot of code that works with %Status values. If you have interacted with persistent classes from an object perspective (%Save, %OpenId, etc.), you have almost certainly seen them. A %Status provides a wrapper around a localizable error message in InterSystems' platforms. An OK status ($$$OK) is just equal to 1, whereas a bad status ($$$ERROR(errorcode,arguments...)) is represented as a 0 followed by a space followed by a $ListBuild list with structured information about the error. $System.Status (see class reference) provides several handy APIs for working with %Status values; the class reference is helpful and I won't bother duplicating it here. There have been a few other useful articles/questions on the topic as well (see links at the end). My focus in this article will be on a few debugging tricks techniques rather than coding best practices (again, if you're looking for those, see links at the end).

14 7
10 1,249


The field test of Caché 2016.2 has been available for quite some time and I would like to focus on one of the substantial features that is new in this version: the document data model. This model is a natural addition to the multiple ways we support for handling data including Objects, Tables and Multidimensional arrays. It makes the platform more flexible and suitable for even more use cases.

13 12
0 2,507
Robert Cemper · May 29, 2019 1m read
Simple Remote Server Control

This example is extracted from a long-running installation. The purpose is to have a simple monitoring of several servers at a rather primitive level. Just slightly more intelligent than a raw PING. But still easy to integrate. It avoids the overkill of information you are often confronted with while you are just interested in the number of active processes or similar basic figures.

13 0
2 484
Sascha Kisser · Oct 24, 2016 4m read
DeepSee Troubleshooting Guide

The goal of this “DeepSee Troubleshooting Guide” is to help you track down and fix problems in your DeepSee project.

If the problem can’t be fixed by following the guidelines, you will at least have enough information to submit a WRC issue with DeepSee Support and provide all the evidence to us, so we can continue the investigation together and resolve it faster!

13 16
1 2,125

Recently, a partner company started to develop an Angular client for their Cache application. Together, we decided to leverage the power of Caché dynamic objects to exchange JSON encoded data between client and server parts. However, we realized that currently there is a gap in Cache JSON implementation that prevents simple use of traditional registered and persistent classes to exposed their data with the same ease as with XML. I wrote a small JSON adapter, that does the job and bridgers the gap. It's purpose is simple expose data described by a regular Cache class in a one-to-one fashion to a %DynamicObject. On the other hand, when a serialized JSON data comes in, it can be easily deserialized into dynamic object and subsequently bound to regular class by the newly created adapter.

13 7
1 1,860

Hi Developers!

Often when we develop some library, tool, package, whatever on InterSystems ObjectScript we have a question, how we deploy this package on the target machine?

Also, we often expect that some other libraries already installed, so our package depends on them, and often on some particular version of it.

When you code on javascript, python, etc the role of packages deployment with dependency management takes package manager.

So, I'm pleased to announce that InterSystems ObjectScript Package Manager available!

13 19
3 2,207

The 2021.2 release of the InterSystems IRIS Data Platform includes many exciting new features for fast, flexible and secure development of your mission-critical applications. Embedded Python definitely takes the limelight (and for good reason!), but in SQL we've also made a massive step forward towards a more adaptive engine that gathers detailed statistical information about your table data and exploits it to deliver the best query plans. In this brief series of articles, we'll take a closer at three elements that are new in 2021.2 and work together towards this goal, starting with Run Time Plan Choice.

It's hard to figure out the right order to talk about these (you can't imagine how often I've reshuffled them in writing this article!) because they fit together in such a nice way. As such, feel free to go on a limb and read these in random order smiley.

13 2
1 521

Last week, we announced the InterSystems IRIS Data Platform, our new and comprehensive platform for all your data endeavours, whether transactional, analytics or both. We've included many of the features our customers know and loved from Caché and Ensemble, but in this article we'll shed a little more light on one of the new capabilities of the platform: SQL Sharding, a powerful new feature in our scalability story.

13 11
1 1,313

The InterSystems Iris Fhirserver running on a Raspberry Pi Raspberry running as a FHIRserver

Raspberry running as FHIRserver

About a year ago I wrote some articles about the installation of the HAPI FHIRserver on a Raspberry Pi. At that time, I only knew the basics of the FHIR standard, little about the technology behind FHIR-servers and not much more about the Raspberry. By trying, failing, giving up and trying again I learned a lot.

13 7
4 628