#Tips & Tricks

InterSystems FAQ rubric

If you want to raise an arbitrary custom error in a TRY block, you can pass an exception with a throw as follows. In the following example, a custom error is raised if Stcount is less than 1.

Class User.Test
{

ClassMethod ExceptionTest()
 {
    try
    {
      // : some codes
      if (Stcount<1) {
          throw ##class(%Exception.General).%New("User-defined error", "5001", "location", "Data at location error")
          // User-created errors are 5001 and above
      }
    }
    catch ex
    {
      write "Errors #", ex.Code, ": ", ex.Name, " : ", ex.

InterSystems FAQ rubric

In InterSystems IRIS, you can create linked tables using commands, instead of using System Explorer > SQL > Wizard > Linked Tables in the Management Portal:

To create a linked table, use the CreateLinkedTable method of the %SYSTEM.SQL.Schema class. See the class reference for details.

To execute it, follow these steps:

set sc = $SYSTEMSQL.Schema.

InterSystems FAQ rubric

There is data, such as execution log data, that you do not want to return to its previous state even if a rollback occurs during a transaction. The above requirement can be met by placing that data in the IRISTEMP database, which will not be rolled back.

Temporary Globals and the IRISTEMP Database

By mapping the table entities you do not want to roll back to this database, you can retain the information after the rollback.

This article is a continuation of the IRIS JSON project and features additional methods and insights.

Let's continue with the instance methods

%GetTypeOf(Key)

This instance method is used to determine the JSON data type of the %DynamicObject or %DynamicArray.

It returns one of the following strings:

USER>Set array = [1,"test",true,12.

InterSystems FAQ rubric

You can check the free disk space at any time using the system utility class: SYS.Database and query: FreeSpace.

Here's how to try it in the IRIS terminal (go to the %SYS namespace and then run it):

zn "%SYS"
set stmt=##class(%SQL.Statement).%New()
set st=stmt.%PrepareClassQuery("SYS.Database","FreeSpace")
set rset=stmt.%Execute()
do rset.%Display()

The output result example is as follows:

*In the command execution example, all databases are located on the same disk, so the free disk space (DiskFreeSpace) returns the same value.

I need to implement a retry policy for an incoming message queue containing thousands of relatively small messages.

Successfully processed messages should be immediately removed from the queue.

If an error occurs while processing a message, the message should be sent back at the end of the queue, and the pause before re-processing this message should increase geometrically (1-2-4-8-16 seconds, and so on). In languages that support the async/await pattern, I'd simply create a delayed timer that triggers a fire-and-forget task. This would prevent blocking the main thread.

Do not let the title of this article confuse you; we are not planning to take the InterSystems staff out to a fine Italian restaurant. Instead, this article will cover the principles of working with date and time data types in IRIS. When we use these data types, we should be aware of three different conversion issues:

1. Converting between internal and ODBC formats.
2. Converting between local time, UTC, and Posix time.
3. Converting to and from various date display formats.

Maybe this is well known but wanted to help share.

Consider that you have the following persistent class defintions

An Invoice Class with a property reference to Provider

Class Sample.Invoice Extends (%Persistent, %Populate)
{
Parameter DSTIME = "AUTO";
Property InvoiceNumber As %Integer(MINVAL = 100000) [ Required ];
Property ServiceDate As %Date(MINVAL = "+$h-730") [ Required ];
Index InvoiceNumber On InvoiceNumber;
Property Provider As Sample.

Previously, we trained our model using machine learning. However, the sample data we utilized was generated directly from insert statements. 

Today, we will learn how to load this data straight from a file.

Hey everyone,

I'm diving deeper into Caché ObjectScript and would love to open a discussion around the most useful tips, tricks, and best practices you’ve learned or discovered while working with it.

Whether you're an experienced developer or just getting started, ObjectScript has its own set of quirks and powerful features—some well-documented, others hidden gems. I’m looking to compile a helpful set of ideas from the community.

InterSystems FAQ rubric

To enable Interoperability functionality after creating a namespace, use the EnableNamespace method of the %EnsembleMgr class:

do ##class(%EnsembleMgr).EnableNamespace()

Hi all,

My team is exploring options for handling timezone offsets in DTL and we’re wondering if there are any built-in methods available — ideally low-code or no-code solutions. Specifically, we're looking for a way to adjust timestamps based on the date and whether Daylight Saving Time (DST) is in effect.

For example, if an HL7 message has an MSH-7 value of 20250518144529, it should be converted to 20250518144529-0500 (Central Daylight Time), but if the timestamp were 20250218144529, it should be 20250218144529-0600 (Central Standard Time).

Reviewing the different articles that I have published, I realized that I needed to explain a very practical functionality within our EMPI (Enterprise Master Patient Index) and it is none other than the notification of registrations and links to systems external to the EMPI.

This functionality is frankly useful in a tool such as EMPI and especially in environments such as healthcare in which it is very common for the same patient to have their data duplicated in different systems and in the end it is necessary to uniquely identify it.

The Good Old Days

The %Library.DynamicObject class has been in IRIS since before it became IRIS. If you have been using it since the Cache days, you may want to brush up on some of its changes.

In Cache 2018, the %Get method only had one argument. It was the key to retrieving from the JSON, meaning that if your JSON object called myObj, it would look like the following:

As we all know, InterSystems is a great company.

Their products can be just as useful as they are complex.

Yet, our pride sometimes prevents us from admitting that we might not understand some concepts or products that InterSystems offers for us.

Today we are beginning a series of articles explaining how some of the intricate InterSystems products work, obviously simply and clearly.

In this essay, I will clarify what Machine Learning is and how to take advantage of it.... because this time, you WILL KNOW for sure what I am talking about.

I added extra OBX segments and I need to renumber OBX 4 so they are sequential.

Is there a way to use a property of the type %Persistent class in a  %ZEN.Component.page class?
Example:

// Data class
Class PersistentClass Extends %Persistent
{
    Property Value As %String;
}

// Page class
Class ClassName Extends %ZEN.Component.page
{
  Property TestProperty As PersistentClass; 
}

The problem is that when using it the described in the example.
The property can be set in a Method like this:

Method DoStuff() As %Status  [ ZenMethod ]
{
    Set result = ##class(HBS.EnsUtil.CompanyFunctions).GetData(.aVariable) // aVariable is of type PersistentClass
    Set .

Is there a generic process for "walking" the structure of a virtual document - eg an HL7 message (EnsLib.HL7.Message) or an XML document (EnsLib.EDI.XML.Document).

At least we'd want to be able to visit all "nodes" (HL7 fields or sub-fields, XML nodes) in the virtual document and be able to work out/generate the Property Path (so we could call "GetValueAt"). 

We can just about come up with something generic for HL7, since it only nests down to 4 levels within each segment, though we're using numeric Property Path's at that point rather than symbolic ones (MSH:1.3 etc).

InterSystems FAQ rubric

This can be done with TRY-CATCH:

 #dim ex As %Exception.AbstractException
 TRY {
    //Code that causes an error
  }
  CATCH ex {
     do ex.Log()
  }

If you use ^%ETN, call it from the BACK entry (BACK^%ETN).

Please also take a look at the related article: How to get application errors (^ERRORS) using a command

Have you ever been editing files in VS Code, but needed to check a global value or run a few ObjectScript commands? Now you can, with no setup required! If you have vscode-objectscript extension version 2.10.0 or later and are connected to InterSystems IRIS 2023.2 or later, you can now open a terminal connection to your server, regardless of where it's located.

Intro

In the process of trying to get more familiar with Objectscript I decided to try to build a general priority queue since I wasn't able to find an implementation anywhere. My though process for implementing this followed this general path.

Binary Heap

My first though to try to make this work quickly was to implement a binary heap and my first attempt at this used a multidimensional to build it. This version was relatively efficient, worked for strings/numbers natively, and worked for objects be letting the user override the comparitor.

Class pqueue.

We have some ObjectScript code in a custom business process:

When Log Trace Events is ticked on the business process in the Production view in the management portal, the argument is obviously computed.

Our question is whether the argument is computed when Log Trace Events is not ticked? Don't want to accidentally include something in a $$$TRACE() statement that takes enough computation to make a performance difference when released to production, even though the final output is not written to the event log.

Hello Community:

Let's go with the last article on how to record yourselves for the Article Contest video bonus.

I'm not going to go into how to do very specific things in editing because it varies depending on the program you use. The keyboard shortcuts and menus are different, but the concept is the same. You are going to use a programme to organise the recorded material, remove the excess and give it structure. Many of these softwares are free (Capcut, Canva and if I'm not mistaken DaVinci had a free version). I've been editing with Adobe Premiere for almost ten years now (wow, I'm getting old), so if you have any questions about this software, feel free to write to me.

Here are some concrete tips:

Hello Community:

Do you want to know how to record yourself without looking like you're speaking from a cave? Are you one of those who say you ‘don't come off well on camera’? 

Today I'm going to share with you some specific tips that I learned after several years of filming interviews for television and networks. I remind you that these are tips in case you are thinking of taking advantage of the Article Contest video bonus. However, they are tips that I'm sure you can use for presenting webinars, video calls and filming yourself in general.

Hi Community,

As you may know, this year's Spanish Technical Articles contest will be in May. I am going to make a series of articles to support you in the creation of your articles, giving tips and tricks. Perhaps they will be useful for the contest you have active in this community as well.

As you may know, one of the bonuses or extra points you can receive is to add a video tutorial to your article. You may not even know how to approach this issue, no problem! I'm here to give you some tips that you can apply not only to the creation of these videos, but to any other.

Hi, this post was initially written for Caché. In June 2023, I finally updated it for IRIS. If you are revisiting the post since then, the only real change is substituting Caché for IRIS! I also updated the links for IRIS documentation and fixed a few typos and grammatical errors. Enjoy :)

In this post, I show strategies for backing up InterSystems IRIS using External Backup with examples of integrating with snapshot-based solutions. Most solutions I see today are deployed on Linux on VMware, so a lot of the post shows how solutions integrate VMware snapshot technology as examples.

Another VSCode "Tips & Tricks" entry -

Do you want to see this option in VSCode?

The latest "Bringing Ideas to Reality" InterSystems competition saw me trawling through the ideas portal for UI problems to have a go at. 

InterSystems FAQ rubric

It can be obtained with a List query of the %SYS.Namespace class.

1. Create a routine like this:

getnsp
   set statement=##class(%SQL.Statement).%New()
   set status=statement.%PrepareClassQuery("%SYS.Namespace","List")
   set resultset=statement.%Execute()
   while resultset.%Next() {
       write resultset.%Get("Nsp"),!
   }
   quit

2. Run it in your terminal

The method of executing class queries introduced in this article can be applied in a variety of cases.

You can see various class queries in the class reference.

The ability to resend messages easily has always been a strong feature of our Interoperability capabilities.

With v2024.3 coming out soon (available already now as Developer Preview) out already we've made this even easier!