$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

The DeclarativeCOS project is a heartfelt cry about programming in the COS language.

The purpose of the project is to draw attention of the public to improving the inner core of COS.

The idea of the project is the support of a laconic syntax for cycles and collections.

So what is this laconic something that I have come up with? Welcome to the examples below!

Examples

The key concept underlying the project is the declarative approach to writing code. You need to specify WHAT should be used and HOW.

Caché offers a number of methods for going through a collection and doing something with its elements. The easiest method uses a while-loop and lets you fulfill the task in an imperative manner. The developer needs to take care of the iterator, jumping to the next element and checking if the loop is within the collection.

Today, I was reading some source code, and encountered the following method signature:

Method SendRequestSync(pRequest As %Library.Persistent, ByRef pResponse As %Library.Persistent)

And I immediately thought, why is there a ByRef?

InterSystems states that Caché supports at least three data models – relational, object and hierarchical (globals). On can work with data presented in relational model in a program written on C# the same way one works with any other relational DB. To work with data presented by object model in C# one needs to use .NET Managed Provider or some kind or ORM. And starting with version 2012.2 one can work directly with globals (or use direct access to hierarchical data) via Caché eXTreme for .NET. 

Developing a Full-Stack JavaScript web app with Caché requires you to bring together the right building blocks. In this third part of this article series I will show how to link our React app to our three back-ends we created in part 2.

It has been noticed that some customers running JAVA programs (for example, FOP) on AIX would see the server eventually running low then out of memory. Customer would notice the system pages heavily and user experience becomes bad. And the server would crash when out of memory.

When the problem happens, we can see in ipcs a lot of shared memory segment marked for deletion (Capital D at the beginning of MODE section). This means they will not disappear until the last process attached to the segment detaches it.

C:\data\backup.bat :

C:\InterSystems\Ensemble\bin\cache -s"C:\InterSystems\Ensemble\Mgr" -U%%SYS ##Class(Backup.General).ExternalFreeze() <C:\data\login.scr 

echo %ERRORLEVEL%

rem note that we need to check errorlevel from highest to lowest here....

if errorlevel 5 goto OK

If you want to dynamically serve images as a property of JSON then there is no perfect encoding solution. One method used frequently is to Base64 encode the image. Whilst there are some negatives to doing this, such as data inflation, there are some positives to working with Base64 images inside the browser.

Let's say you have an image placeholder on a web page...

Several years ago everyone got mad about BigData – nobody knew when smallish data will become BIGDATA, but all knows that it’s trendy and the way to go.

Those of you who keep an eye on developments in the mainstream of IT will be aware that a major upheaval has been occurring over the last 5 or so years, in which JavaScript has exploded in popularity and importance.  Largely as a result of its server-side incarnation - Node.js - it has broken free of just being the scripting language that you use in web browser, to becoming the world's most popular language and enterprise technology of choice.

Hello,

We are sometimes asked for examples of how to do 3rd party SQL database selects/updates/inserts/stored procedures from an Ensemble SQL Business Operation.

In the attached file there are 4 sample Ensemble Operations that demonstrate four different types of transactions with an external SQL DB:

Question:

How can I get a value of a setting of a Production item programmatically?

Answer:

You can use one of the API methods of the Ens.Director class, for example:

Ens.Director:GetItemSettingValue()

For example –

Framing refers to the characters that mark the start and end of an HL7 message (or other types of framed messages).  Most HL7 services and operations have a Framing setting that allows the user to define this framing.  The most common choices are available as defaults, but with the AsciiMM/NN setting, components can be configured to recognize any framing characters.