$LIST string format and %DynamicArray and %DynamicObject classes

IRIS, and previously Cache, contain several different ways to create a sequence containing a mixture of data values. A data sequence that has been available for many years is the $LIST string. Another more recent data sequence is the %DynamicArray class, which along with the %DynamicObject class, is part of the IRIS support for JSON string representation. These two sequences involve very different tradeoffs.

$LIST String Format

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Stefan Wittmann · Aug 25, 2016
JSON changes in Caché 2016.2

As Bill has mentioned earlier in his post, we have carefully reviewed the JSON capabilities and made some adjustments to ensure they deliver the best benefit to you. In this post, I am going to describe the modifications in more detail and provide guidance for you to understand the implication for your code base.

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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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++Update: August 2, 2018

This article provides a reference architecture as a sample for providing robust performing and highly available applications based on InterSystems Technologies that are applicable to Caché, Ensemble, HealthShare, TrakCare, and associated embedded technologies such as DeepSee, iKnow, Zen and Zen Mojo.

Azure has two different deployment models for creating and working with resources: Azure Classic and Azure Resource Manager. The information detailed in this article is based on the Azure Resource Manager model (ARM).

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Astronomers’ tools

5 years ago, on December 19, 2013, the ESA launched an orbital telescope called Gaia. Learn more about the Gaia mission on the official website of the European Space Agency or in the article by Vitaly Egorov (Billion pixels for a billion stars).

However, few people know what technology the agency chose for storing and processing the data collected by Gaia. Two years before the launch, in 2011, the developers were considering a number of candidates (see “Astrostatistics and Data Mining” by Luis Manuel Sarro, Laurent Eyer, William O’Mullane, Joris De Ridder, pp. 111-112):

Comparing the technologies side-by-side produced the following results (source):

Technology Time
DB2 13min55s
PostgreSQL 8 14min50s
PostgreSQL 9 6min50s
Hadoop 3min37s
Cassandra 3min37s
Caché 2min25s

The first four will probably sound familiar even to schoolchildren. But what is Caché XEP?

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I'm pleased to announce a major release of the InterSystems Server Manager extension. It has gained a UI!

Read more at Open Exchange.

Right now version 2.0 is like an aircraft at the start of the runway (remember those days before COVID-19?), waiting for the control tower to give final clearance. Will you be an early adopter, downloading the VSIX from GitHub, installing it into your VS Code, and posting back here to confirm that we haven't left anything critical behind at the gate? Then I'll push the throttles forward, publish to Marketplace, and we'll all be on our way.

Server Manager 2.0 is my entry for the current contest. If you like it maybe you'll vote for me it.

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Rob Tweed · Dec 20, 2021 1m read
Holiday Reading: What Lies Beneath!

For those of you who might be new to IRIS, and even those who have used Cache or IRIS for some time but want to explore beyond its usually-assumed boundaries and practices, you might want to dive into this detailed exploration of the database engine that is at its heart, and discover just what you can really do with it, going way beyond what InterSystems have done with it for you.

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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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The %Net.SSH.Session class lets you connect to servers using SSH. It's most commonly used with SFTP, especially in the FTP inbound and outbound adaptors.

In this article, I'm going to give a quick example of how to connect to an SSH server using the class, describe your options for authenticating, and how to debug when things go wrong.

Here's an example of making the connection:

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Despite the fact that InterSystems has long recommended using external backup tools, many users have opted to use the internal Online Backup facility, which is included in all distributions of InterSystems products (IRIS Data Platform, Caché, etc.). The reasons why are quite obvious:

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Robert Cemper · Apr 25, 2020 2m read
Semi-Persistent Classes and Tables

If you define a Persistent Class / Table the class compiler generates for you an appropriate Storage definition.
A different option is to define a SQL mapping for an already existing Global storage. This has been excellently
explained already in a different series of articles. The Art of Mapping Globals to Classes 1 of 3

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I'm doing a query in SQL and I need to sort my data by some non-repeated field.

Unfortunately, my data is grouped in a way that I cannot guarantee that any column will not have repeated data, so one solution would be to take the row number.

Also, the Cache is not accepting Row_Number () in my querry and I would like to know if there is another solution to return line numbers or some way to add this function to the Cache.

Best regards.

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Cache tricks

Several years ago, long before Developer Community Portal was launched, I published a series of Caché tricks at one of Czech web sites. In this article, I’m posting translated version of one of them.

Capturing output of someone else’s methods or routines

Suppose you, or someone else created a useful method or routine, that was producing some computation that you’d like to benefit from, but the routine was writing output to process principal device.

You would like to use the data, but you need it not written to a device, but assigned to a variable. And, for any reason, you can’t modify the code. What can you do?

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I wanted to share a little tidbit which is in the Studio documentation (http://docs.intersystems.com/cache20152/csp/docbook/DocBook.UI.Page.cls?...) but many people who have been using the InterSystems Studio for a long time missed the addition of this *very* useful feature, and every time I mention this to an audience I see at least one face light up because of how excited they are to learn about it!

Within Studio, the Output pane (View -> Output) is actually misnamed. It is actually an Input/Output window which can be used to run Caché ObjectScript commands!

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