Beginner tag unites articles and questions for those who are getting started with InterSystems Data Platform
InterSystems IRIS is, among other things, a relational DBMS. This is why it supports all standard SQL indexes together with some additional ones. For beginners, the variety of index types in IRIS can feel a bit overwhelming. Thus, the goal of this article is to clarify when to use each and provide clear code examples.
In the modern world, data is rarely uniform. Applications often require the structural rigidity of a relational database, the flexibility of a document store, and the performance of a high-speed key-value storage. Luckily, InterSystems IRIS solves this complexity by providing a single, unified engine that natively supports multiple distinct data models:
Crucially, all of these models access exactly the same physical data.
To illustrate this approach, let's examine all these data models using the same conceptual structure: The Record of Patient P101 (John Doe).
If you start with InterSystems ObjectScript, you will meet the XECUTE command.
And beginners may ask: Where and Why may I need to use this ?
The official documentation has a rich collection of code snippets. No practical case.
Just recently, I met a use case that I'd like to share with you.
When you build an IRIS container with Docker, then, in most cases,
you run the initialization script
iris session iris < iris.script
This means you open a terminal session and feed your input line-by-line from the script.
And that's fine and easy if you call methods, or functions, or commands.
Hi folks!
Our community is growing rapidly, and the knowledge base is incredibly vast. Whether you're a newbie, confused, and unsure where to start, or a seasoned IRIS veteran who occasionally forgets a few basic rules (it's normal and happens to everyone!), you'll find this brief overview of IRIS basics and all its wonders useful.
Here I'd like to begin a series of articles dedicated to this topic.
There will be eight main topics in total:
Each of them will consist of four parts: Courses, Community articles, Documentation, Applications
This particular part will cover InterSystems ObjectScript. For your convenience, all categories will be hidden under a spoiler.
Hey Community!
We're happy to share the first video in the "InterSystems Instruqt Walkthroughs" series on our InterSystems Developers YouTube:
⏯ Data Models of InterSystems IRIS - InterSystems Instruqt Walkthrough
to dismount/mount a database, use Dismount() and Mount() methods in SYS.Database class available in %SYS namespace.
NB: the database ID is its Directory
You'll find some examples of how to dismount/mount and check if a database is mounted (Mounted=1) or not (Mounted=0), and quickly see all the attributes of a database (via zwrite)
%SYS>set db="/opt/irisapp/data"
%SYS>w ##class(SYS.Database).%OpenId(db).Mounted
1
%SYS>w ##class(SYS.Database).%OpenId(db).Dismount()
1
%SYS>w ##class(SYS.Database).%OpenId(db).Mounted
0
%SYS>w ##class(SYS.Database).%OpenId(db).Mount()
1
%SYS>w ##class(SYS.Database).%OpenId(db).Mounted
1
%SYS>zw ##class(SYS.Database).%OpenId(db)
+----------------- general information ---------------
| oref value: 3
| class name: SYS.Database
| %%OID: $lb("/opt/irisapp/data","SYS.Database")
| reference count: 2
+----------------- attribute values ------------------
| %Concurrency = 0 <Set>
| BlockFormat = 2
| BlockSize = 8192 <Set>
| Blocks = 780288
| BlocksPerMap = 62464
| ClusterMountMode = 0 <Set>
| ClusterMounted = 0 <Set>
| CurrentMaps = 13
| Directory = "/opt/irisapp/data/" <Set>
| DirectoryBlock = 3
| EncryptedDB = 0 <Set>
| EncryptionKeyID = ""
| Expanding = 0
| ExpansionSize = 0 <Set>
| Full = 0
| GlobalJournalState = 3 <Get,Set>
| InActiveMirror = 0
| LastExpansionTime = "09/06/2023 20:00:01"
| MaxSize = 0 <Set>
|MirrorActivationRequired = 0
| MirrorDBCatchup = 0
| MirrorDBCreatedNew = 0
| MirrorDBName = ""
| MirrorDBPaused = 0
| MirrorFailoverDB = 0
| MirrorNoWrite = 0
| MirrorObsolete = 0
| MirrorSetName = ""
| Mirrored = 0
| Mounted = 1
| NewGlobalCollation = 5 <Set>
|NewGlobalGrowthBlock = 50 <Set>
| NewGlobalIsKeep = 0 <Set>
|NewGlobalPointerBlock = 16 <Set>
| NumberOfConfigDB = 0
| ROReasonCode = 0
| ROReasonText = ""
| ReCreate = 0
| ReadOnly = 0 <Set>
| ReadOnlyMounted = 0
| Reinitialize = 0
| RequestSize = 0
| ResourceName = "%DB_IRISAPP-DATA"
|RunCatchupDBOnCreate = 1
| SFN = 6
| Size = 6096 <Set>
| Skeleton = 0
| SparseDB = 0
+-----------------------------------------------------
%SYS>
I know IRIS has a built-in testing framework, but I'm not sure how to write tests that validate the full message flow through a Production without depending on external systems. Do you mock Business Operations? Is there a pattern you use to test integration scenarios in an isolated and repeatable way?
I understand that Business Rules can be used to route or transform messages without touching code. But I'm not clear on when it's better to use a Business Rule versus handling the logic directly inside a BPL or a custom BP class. What criteria do you use to decide between them?
If I need to add or change properties in a message class that is already being used by a running Production, what is the safest way to do this? Are there risks with existing messages in the queue or in the message store? Is there a migration strategy the community recommends?
I've seen that %JSON.Adaptor makes it easy to serialize and deserialize objects to JSON, but I've also seen people building custom serialization logic. Are there scenarios where %JSON.Adaptor falls short, such as handling nested objects, null values or custom field naming conventions? What has been your experience?
In .NET projects I usually rely on appsettings per environment. In IRIS Productions, settings are stored per component and seem tied to the namespace. What strategies do you use to manage different configurations across environments without manually changing settings every time you promote a Production?
I have several Business Operations that share similar behavior, like building HTTP headers or parsing a specific response format. In C# I would extract this into a service class or a base class. What is the recommended way to do this in IRIS? Should I use a utility class, a common superclass, or is there another pattern the community prefers?
I have a Business Process that needs to call an external API that may take several seconds to respond. I'm worried that keeping the BP blocked waiting for the response could affect the overall Production throughput. Is there a recommended pattern for handling async calls inside a BPL or custom BP class to avoid this kind of bottleneck?
What tools or techniques do you use to debug a Production during development? I know the Management Portal shows the message queue and event log, but I'm wondering if there are better ways to trace a message through the full BS > BP > BO flow without relying only on logs.
When building a Production, should I create separate message classes for each integration flow, or is it acceptable to reuse generic request/response classes across different Business Operations? I'm trying to understand how to keep things organized as the number of integrations grows.
What is the recommended way to handle errors inside a Business Process in IRIS? Should I use Try/Catch within the BPL, return error responses to the caller, or rely on the built-in retry mechanism of the Production? Looking for guidance on what's considered good practice.
For those who learned Caché ObjectScript from scratch: what kind of personal or practice projects did you build to get comfortable with the language? I come from a C# background and I'm looking for project ideas that are small enough to be feasible but meaningful enough to actually teach the core COS concepts.
The recently published tutorial "Introduction to InterSystems Data Studio" inspired me to check out this product. And I think it’s an interesting look at how to manage a data fabric without deep-diving into complex code. It allows you to connect disparate data silos, transform the data through automated pipelines, and load it into a unified environment for analysis. So, I decided to write up an example of how you can use it. Basically, I'll walk you through the tutorial in case you don't have time to do it on your own. Though I would definitely suggest you actually follow the tutorial - it has lots of useful information.
To see how it works, I stepped into the shoes of a system administrator, logging in with the provided credentials to explore the interface. The layout centers on a few core pillars: defining where data comes from, cataloging its structure, and building automated "recipes" to move it into production.
And the very first step is to establish a connection to my data.
When we need to integrate Caché/IRIS with other relational databases, one common question arises: “How do I set up the JDBC connection?”.
The official documentation doesn’t always provide a straightforward step-by-step guide, which can be frustrating, especially for beginners.
In this article, I’ll walk you through the entire process of configuring a JDBC connection with MySQL, from downloading the connector to linking tables in Caché/IRIS.
Note: JDBC connections in Caché/IRIS have some limitations, especially regarding caching and the use of ResultSet
Despite the fact that LOCK (docs) is a foundational part of InterSystems IRIS, responsible for concurrency, there is not a lot of discussion on the Developer Community about it. Which is understandable, considering it's stable and fairly low-level command. In this article, I will show a simple example of how to use locks with interoperability.
I joined InterSystems less than a year ago. Diving into ObjectScript and IRIS was exciting, but also full of small surprises that tripped me up at the beginning. In this article I collect the most common mistakes I, and many new colleagues, make, explain why they happen, and show concrete examples and practical fixes. My goal is to help other new developers save time and avoid the same bumps in the road.
The issue: ObjectScript/IRIS ships with many system classes and packages (%Library, %SYS, %Persistent, %SQL, etc.).
Hi Community,
If you’re new to InterSystems, check out the InterSystems Developer Hub.
Start working with InterSystems technologies — install InterSystems IRIS, connect to it, run something real, or try products directly in a browser-based interactive environment (no setup required).
If you’re wondering where to begin, here’s what you’ll find there:
Developer Onboarding Guide — a structured walkthrough of what InterSystems IRIS is and how to set it up
Quickstarts — short, practical guides to get you from zero to a working setup:
Hi, Community!
Are you working with large tables? See how partitioning helps you manage and query your data:
In this series of articles, I'd like to present and discuss several possible approaches toward software development with InterSystems technologies and GitLab. I will cover such topics as:
In the first article, we covered Git basics, why a high-level understanding of Git concepts is important for modern software development, and how Git can be used to develop software.
Hi Community,
Are you looking for resources to help your team onboard? Use these guides to get started!
Updated 04/17/26
Hi Community,
Need to find the most relevant onboarding for your HealthShare Unified Care Record® team? Maximize your team's knowledge and success by diving into this curated list of offerings from InterSystems Learning Services—which includes online and in-person training for a variety of roles in your organization.
Updated 04/17/26
Hi Community,
Looking for a way to onboard your team with InterSystems IRIS® for Health? Unlock the full potential of this platform by using these InterSystems learning resources. With a mix of online and in-person training, you can support various roles in your organization and equip your team for success.
Updated 04/16/26
Hi Community,
You can unlock the full potential of InterSystems IRIS—and help your team onboard—with the full range of InterSystems learning resources offered online and in person, for every role in your organization. Developers, system administrators, data analysts, and integrators can quickly get up to speed.
Hi, Community!
Here's another way AI can speed up your processes—take a look! 👇
Generating Transformation Descriptions with the DTL Explainer
Hi Community,
The InterSystems Learning Website has many important iterative courses.