Hello!

This article is a small overview of a tool that helps to understand classes and their structure inside the InterSystems products: from IRIS to Caché, Ensemble, HealthShare.

In short, it visualizes a class or an entire package, shows the relations between classes and provides all the possible information to developers and team leads without making them go to Studio and examine the code there.

If you are learning InterSystems products, reviewing projects a lot or just interested in something new in InterSystems Technology solutions — you are more than welcome to read the overview of ObjectScript Class Explorer!

190
2 35 4,580
Article
Robert Cemper · Jul 4, 2020 4m read
Editor Archaeology

During the development of the Terminal Multi-Line Command Editor I discovered in my IRIS installation
a piece of software that I just can classify as a historic artifact. And it is still fully operational !!!

As it dates back to times before InterSystems was founded in 1978 you may understand my surprise.
I personally stepped into that environment in 1978 and used it then for daily work.

160
0 5 214
Article
Robert Cemper · Jun 10, 2019 1m read
A more useFull Object Dump
This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

During testing your code you are often confronted with the need to examine
the actual content of an object. Either using ZWRITE or $system.OBJ.Dump()
you get a picture of simple properties as "--- attribute values ---"
while "--- swizzled references ---" are more confusing than informative
and with "--- calculated references ---" you are just left in the lurch.

160
1 3 584

Preface: our small, but very ambitious company called “Black Mushroom Studio” came up with an idea for an e-commerce project and a mobile app that would let users pay for certain goods/services via a payment aggregator.

 

What we had initially: an Android app skeleton that, of course, liked communicating via HTTP and JSON, and a payment system with an API – web services with SOAP content.

 

Goal: make it all work together.

160
0 2 1,293

GraphQL is a standard for declaring data structures and methods of data access that serves as a middleware layer between the client and the server. If you’ve never heard about GraphQL, here is a couple of useful online resources: here, here and here.

In this article, I will tell you how you can use GraphQL in your projects based on InterSystems technologies.

150
10 24 1,789

As you know in Caché / IRIS you have the possibility to define a property as Multidimensional as documented here:
https://docs.intersystems.com/iris20201/csp/docbook/DocBook.UI.Page.cls?KEY=GOBJ_proplit#GOBJ_proplit_multidim
and the explanation of how to use it
https://docs.intersystems.com/iris20201/csp/docbook/Doc.View.cls?KEY=GOBJ_proplit#GOBJ_proplit_multidim_values

Though the access is quite comfortable (in traditional COS sense) there are 2 main restrictions that hurt:

#1) It is not saved to disk unless your application includes code to save it specifically.
#2) It cannot be stored in or exposed through SQL tables
   there are some more
I'll show how to overcome these limits

140
2 0 258
Article
Robert Cemper · Feb 8, 2019 2m read
Client for WebSockets based on Node.js

WebSockets as a communication technology wins increasing importance.
In the SAMPLES namespace, you find a nice example for running a WebSocket Server.
There is also a useful example for a Browser Client. JavaScript does most of the work. 

My point is:
How to consume the output of a WebSocket Server in your application?

140
0 2 430
Article
Robert Cemper · Mar 26, 2019 2m read
Synchronize Data with DSTIME

 For Data Synchronization inside Caché you have a range of ways to synchronize objects and tables.
At DB level you can use Shadowing  or Mirroring 

This works excellent and if you need just a part of your data to be synchronized you may split your
data into smaller pieces using Global mapping 
Or if you need bi-directional synchronization on Class/Table level you can use the Object Synchronization Feature 


The limit of all these excellent features:
They just work from Caché/IRIS to Caché/IRIS.

130
2 6 487

This short article was motivated by a problem of one of my customers. They use Ensemble to integrate many systems, some of them use just plain files.

So they naturally selected File Outbound Adapter to write into target file. Things were running smoothly for years, until recently, when the volume of data being written to the file reached large size of tens of megabytes. The operation took around half an hour to complete, causing timing problems where subsequent operations within the process had to wait, and third party system was not happy to wait so long.

130
0 2 566
Article
Robert Cemper · May 29, 2019 1m read
Simple Remote Server Control

This example is extracted from a long-running installation. The purpose is to have a simple monitoring of several servers at a rather primitive level. Just slightly more intelligent than a raw PING. But still easy to integrate. It avoids the overkill of information you are often confronted with while you are just interested in the number of active processes or similar basic figures.

The code is available for you here 

This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

130
2 0 423
Article
Robert Cemper · May 30, 2019 2m read
Background Jobs over ECP
This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

Running a Background Job using JOB command is a well-known feature.
Using ECP to distribute databases to several servers is also well know.
But using the combination of both to run a process on a different server
seems to be a rare case.

130
1 0 403
Article
Timothy Leavitt · Jul 8, 2020 7m read
Tips for debugging with %Status

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).

130
8 7 787

In my earlier article on Adopting Bitmaps I described the technique already.
Now you can find a code example also on Open Exchange.

This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

120
1 0 230
Article
Robert Cemper · Apr 26, 2020 5m read
Materialized Views

A VIEW in SQL is basically a prepared SQL statement.
It has to be executed and assembled like any other SQL query.
MATERIALIZED VIEW means that the content is collected before hands and can be retrieved rather fast.
I saw the concept first with my favorite competitor named O* and they made a lot of noise about it.

  { favorite: because I could win every benchmark against them devil }

120
1 3 382
Article
Robert Cemper · Jul 29, 2020 5m read
SQL for ^ERROR Global
This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

Standard error logs in IRIS / Caché / Ensemble are written global ^ERRORS.
As this piece dates back some decades back to previous millennium its structure
is far from the typical SQL storage structures.

110
2 16 442
Article
Robert Cemper · Nov 21, 2020 3m read
ObjectScript over ODBC
This is a coding example working on IRIS 2020.1 and on Caché 2018.1.3 
It will not be kept in sync with new versions      
It is also NOT serviced by InterSystems Support !   
Every now and then you may encounter a situation where for various reasons
ODBC is the only option to access a remote system. Which is sufficient as long as you need to examine or change tables.
But you can't directly execute some commands or change some Global.

 
Special thanks @Anna Golitsyna for inspiring me to publish this.

110
0 0 257
Article
Robert Cemper · Jul 20, 2020 2m read
SPOOL as SQL Table

 

This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

Background

Device #2 named SPOOL dates back to the predecessors of Caché and IRIS
It was the first "%Stream" like option to buffer output before printing.
It is also the first and still today the most simple way of output redirection.

110
0 0 193