Hi everyone.

This is a full example how to use a %ScrollableResultSet for results pagination using %DynamicQuery:SQL and build a JSON response including page details.

Feel free to use, share, comment or improve it.

Kind Regards

%objlasterror is a useful reference to the last error.

Every time $$$ERROR is called, %objlasterror is set to a result of this call.

It's important in cases where you want to convert exception to status:

Try {
   //  quality code
} Catch ex {
   Set sc = $g(%objlasterror, $$$OK)
   Set sc = $$$ADDSC(sc, ex.AsStatus())
}

Because AsStatus calls $$$ERROR under the wraps, the order is important, first you need to get %objlasterror and convert exception after that.

Hi, Community!

Want to share with you one debugging approach from the Russian forum.

Suppose I want to debug the application and I want it to stop the execution on a particular line.

I add in code this line:

l +d,-d

When I want to start debugging in this line I block d in terminal

USER> l +d

And execute the app.

The app stops on this line and lets me connect to it with Studio debugger.

Hi!

It is often necessary to run some external command such as a python program or a shell script from inside Caché/Ensemble. There are three ways of doing this:

There are still so many syntax highlighting errors in Atelier, which still exists from first beta public release.

Developing a Full-Stack JavaScript web app with Caché requires you to bring together the right building blocks. Previously, I outlined the basic steps to install and connect Node.js to Caché and make it's powerful multi-model database capabilites available for use with Node.js. You can use Caché as a NoSQL-, document- (with unique key-level access!), SQL- and object-database with Node.js. When developing JavaScript applications, you'll see how powerful this combination is and makes Caché a perfect fit for Node.js.

In the first part of this article series I will show how to get started with the React framework, one of the most popular frameworks currently taking over front-end development. In the next parts you'll learn how to connect a basic web app to a Caché back-end.

You'll see, it's very easy to get started with this technology - you can even compare the amount of basic knowledge you need to COS because you only need to know a few basic concepts to start!

Hi Developers!

As you know InterSystems IRIS Interoperability solutions contain different elements of the solution, such as: production, business rule, business process, data transformation, record mapper. And sometimes we can create and modify these elements with UI tools. And of course we need a handy and robust way to source-control the changes made with UI tools.

For a long time this was a manual (export class, element, global, etc) or cumbersome settings procedure, so the saved time with source-control UI automation was competing with lost time to setup and maintain the settings.

Now the problem doesn't exist any more. With two approaches: package first development and usage of IPM package git-source-control by @Timothy Leavitt
.

The details are below!

There's plenty of goodness in the %-packages InterSystems supplies, and it seems that every new version of Caché brings something new. The browser-based class documentation (a.k.a. Documatic) generally provides a good level of information, but on the basis that "a picture is worth a thousand words" I sometimes want a diagram.

For example, when trying to navigate the %Dictionary package for a project that needed to find out about class definitions, here's one of the UML class diagrams I created.

tl;dr I have discovered that using $THIS in a very specific way will make persistent objects go stale.

I found that it only happens when using $get on an array that contains the OID reference of $THIS. I assume that this is an unwanted feature and have raised a WRC. The problem can be recreated following the steps below, I have also posted the workaround that I am currently testing and looks to be working fine.

1. Create a persistent class...

In this article, I will show how you can easily containerize .Net/Java Gateways.

For our example, we will develop an Integration with Apache Kafka.

And to interoperate with Java/.Net code we will use PEX .

Architecture

Our solution will run completely in docker and look like this:

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?

This article created as side effect of preparations to the longer set of articles about simple, but still handy MapReduce implementation in Caché. I was looking for relatively easy way to pass arguments to (potentially) multiple targets via remote calling facilities. And after several attempts I have realized that we do have very powerful mechanism in the Caché ObjectScript which might be of particular help here – dynamic dispatch for methods and properties.

Introduction

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).