Globals, these magic swords for storing data, have been around for a while, but not many people can use them efficiently or know about this super-weapon altogether.

If you use globals for tasks where they truly shine, the results may be amazing, either in terms of increased performance or dramatic simplification of the overall solution (1, 2).

Globals offer a special way of storing and processing data, which is completely different from SQL tables. They were first introduced in 1966 in the M(UMPS) programming language, which was initially used in medical databases. It is still used in the same way, but has also been adopted by some other industries where reliability and high performance are top priorities: finance, trading, etc.

Later M(UMPS) evolved into Caché ObjectScript (COS). COS was developed by InterSystems as a superset of M. The original language is still accepted by developers' community and alive in a few implementations. There are several signs of activity around the web: MUMPS Google group, Mumps User's group), effective ISO Standard, etc.

Modern global based DBMS supports transactions, journaling, replication, partitioning. It means that they can be used for building modern, reliable and fast distributed systems.

Globals do not restrict you to the boundaries of the relational model. They give you the freedom of creating data structures optimized for particular tasks. For many applications reasonable use of globals can be a real silver bullet offering speeds that developers of conventional relational applications can only dream of.

Globals as a method of storing data can be used in many modern programming languages, both high- and low-level. Therefore, this article will focus specifically on globals and not the language they once came from.

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Article
· Jul 26, 2017 3m read
What is APM?

What is APM?

I am talking about Application Performance Management at global summit, and several people have asked what that means so it is time for a bit of an explanation.

APM or Application Performance Management (sometimes referred to as Application Performance Monitoring) has a very good (if complicated) explanation on Wikipedia but to me it just means looking at performance from the users’ point of view and the level of service provided to them.

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Article
· Oct 18, 2016 7m read
Macros in the InterSystems Caché

In this article I would like to tell you about macros in InterSystems Caché. A macro is a symbolic name that is replaced with a set of instructions during compilation. A macro can “unfold” in various instruction sets each time it is called, depending on the parameters passed to it and activated scenarios. This can be both static code and the result of ObjectScript execution. Let's take a look at how you can use them in your application.

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· Sep 2, 2016 2m read
Advanced URL mapping for REST

By now it's a commonplace how to implement a basic REST API in Caché and there is good documentation about it here: REST in Caché

A question that comes up from time to time is:

How can I make a parameter in my REST url optional?

Simply put, is it possible to create a URL map in Caché that maps a URL like this:

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· Jul 7, 2017 19m read
Indexing of non-atomic attributes

Quotes (1NF/2NF/3NF)ru:

Every row-and-column intersection contains exactly one value from the applicable domain (and nothing else).
The same value can be atomic or non-atomic depending on the purpose of this value. For example, “4286” can be
  • atomic, if its denotes “a credit card’s PIN code” (if it’s broken down or reshuffled, it is of no use any longer)
  • non-atomic, if it’s just a “sequence of numbers” (the value still makes sense if broken down into several parts or reshuffled)

This article explores the standard methods of increasing the performance of SQL queries involving the following types of fields: string, date, simple list (in the $LB format), "list of <...>" and "array of <...>".

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A few customers have seen this happen, so I thought it would be worth mentioning here on the Developer Community. This could affect users running versions between 2014.1.3 and latest who install or upgrade Wireshark. There is a bug in the Visual C++ 2013 redistributable shipped with the current Wireshark 2.2.1.

This is from Microsoft’s bug report https://support.microsoft.com/en-us/kb/3138367 :

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This is a translation of the following article. Thanks [@Evgeny Shvarov] for the help in translation.

This post is also available on Habrahabrru.

The post was inspired by this Habrahabr article: Interval-associative arrayru→en.

Since the original implementation relies on Python slices, the Caché public may find the following article useful: Everything you wanted to know about slicesru→en.

Note: Please note that the exact functional equivalent of Python slices has never been implemented in Caché, since this functionality has never been required.

And, of course, some theory: Interval treeru→en.

All right, let’s cut to the chase and take a look at some examples.

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Recently I was conducting a remote support session with a site. The desktop they were sharing with me was on a PC configured with German as the native language. Since my German is rather rusty, and virtually non-existent when it comes to computing terms, I was glad to be able to switch the Portal session into English.

This is done from the page that appears when you use the About link:

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In addition to its general security, Caché offers SQL security with a granularity of a single row. This is called row-level security. With row-level security, each row holds a list of authorized viewers, which can be either users or roles. By default access is determined at object modification Some time ago I became interested in determining row-level security at runtime. Here's how to implement it.

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I needed to use the OnGetNodeInfo callback of a Zen <dynaTree>, because this seems to be the only way to control the style separately for different levels of the tree. This post describes two discoveries I made.

How a dynaTree builds a tree via the OnGetNodeInfo callback

When you use a dynaTree with the OnGetNodeInfo callback, the dynaTree creates a series of nodes and displays them top to bottom in the order they were created.

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or "Things are going to break"

We left our application over the weekend, secure in the knowledge that it was returning data from our primary persistent class, User.Widget. However, Widgets Direct are the premier supplier of both Widgets AND Widget Accessories, so we should really start working on adding these Accessories to our application.

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· May 25, 2017 2m read
The Interns are Coming!

The Data Platforms department here at InterSystems is gearing up for this year's crop of interns, and I for one am very excited to meet them all next week!

We've got folks from top technical colleges with diverse specialties from hard core engineers to pure computer scientists to mathematicians to business professionals. They come from countries around the world like Vietnam, China, and Finland and they all come with impressive backgrounds. We're sure they will do very well this summer.

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· May 22, 2017 1m read
WebSockets v REST?

Most frameworks support either REST or WebSockets, and don't make it easy to switch between the two, and/or support both styles of application at the same time. WebSockets offer many advantages over REST, eg:

- most benchmarks show WebSocket messaging to be significantly faster than over HTTP

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· May 20, 2017 10m read
Localization in Caché DBMS

This is a translation of the following article. Thanks @Evgeny Shvarov for the help in translation.

Let's assume that you wrote a program that shows "Hello World!", for example:

  write "Hello, World!"

The program works and everyone is happy.

With time, however, your program becomes more complex, gets more features and you eventually need to show the same string in different languages. Moreover you don't know the number and names of these languages.

The spoiler below contains a description of how the task of multi-language localization is solved in Caché.

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