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#Data Model

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A database model is a type of data model that determines the logical structure of a database and fundamentally determines in which manner data can be stored, organized and manipulated. The most popular example of a database model is the relational model, which uses a table-based format.

Learn more.

Hi guys!

As you know there are two (at least) ways to get the stored value of the property of InterSystems IRIS class if you know the ID of an instance (or a record).

1. Get it by as a property of an instance with "Object access":

ClassMethod GetPropertyForID(stId As %Integer) As %String

{

set obj=..%OpenId(stId)

return obj.StringData

}

2. Get it as a value of a column of the record with "SQL access":

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Hi, Community!

Suppose I have class A with properties P1 and P2.

I want to introduce class B, which would have same records as Class A, but only one property - P2.

What is the easiest way to manage it assuming that I would like to use Class A to add records and be available for any operations to Users with Role A.

And I would like to introduce class B for Users with role B for read-only access. Preferably they shouldn't even be aware of Class A and P1 existence .

What is the easiest way to introduce it and manage it?

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Let's consider you would like to efficiently store your historical data in a similar structure than the one used for your current data, but without sharing the same physical storage (ie : not in the same global). What is the most efficient way to do it ?

Below a simple class of your current data :

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Hi

I have an Ensemble Application with many classes and relationships between those classes.

I need a tool that can connect to Cache/Ensemble and create a visual ERD from the class definitions within a particular Cache Namespace

MS-Access is one option but it does not automatically create the relationship connectors between classes

Any suggestions

Nigel Salm

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How to find a global's original namespace ? Potentially mapped from a different namespace .

I have a global ^Custom that exists in multiple namespaces but it could mapped from namespace Drone(A) to Launch(B)

Without access to Cache management portal how to find where is my global located using cache code ?

Like if ^Custom == ^[Drone]Custom ??

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Article
· Dec 20, 2021 1m read
Holiday Reading: What Lies Beneath!

For those of you who might be new to IRIS, and even those who have used Cache or IRIS for some time but want to explore beyond its usually-assumed boundaries and practices, you might want to dive into this detailed exploration of the database engine that is at its heart, and discover just what you can really do with it, going way beyond what InterSystems have done with it for you.

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Article
· Aug 2, 2022 8m read
Data models in InterSystems IRIS

Before we start talking about databases and different data models that exist, first we'd better talk about what a database is and how to use it.

A database is an organized collection of data stored and accessed electronically. It is used to store and retrieve structured, semi-structured, or raw data which is often related to a theme or activity.

At the heart of every database lies at least one model used to describe its data. And depending on the model it is based on, a database may have slightly different characteristics and store different types of data.

To write, retrieve, modify, sort, transform or print the information from the database, a software called Database Management System (DBMS) is used.

The size, capacity, and performance of databases and their respective DBMS have increased by several orders of magnitude. It has been made possible by technological advances in various areas, such as processors, computer memory, computer storage, and computer networks. In general, the development of database technology can be divided into four generations based on the data models or structure: navigational, relational, object and post-relational.

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Hi

Just curious to know about the pros and cons of Parent/Child Vs One/Many.

We do use a bit of both.
One big reason we use Parent child is we feel if we delete one global, it gets rid of all child data too and all parent child data is stored in one global. Much easier to manage.

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Hi Developers!

Here're the technology bonuses for the InterSystems Multi-Model Contest that will give you extra points in the voting:

  • InterSystems IRIS BI
  • InterSystems IRIS NLP
  • IntegratedML
  • Real data usage
  • InterSystems Reports
  • ZPM Package deployment
  • Docker container usage

See the details below.

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Question
· Mar 5, 2019
PrimaryKey vs Idkey

Just wondering an Insight in the difference between these two indexes

IdKey / PrimaryKey
=================

Property Identifier As %Integer

Index Index1 on Identifier [Idkey]

Index Index2 on Identifier [PrimaryKey]

What's the difference?

1. If I don't have Index1 and only have Index2, then cache does still make its own id.
So how and why do I ever use the PrimaryKey. In Joins ??

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Hi

Totally new to IRIS and Cache.

Trying to evaluate it and work out how we could use it.

As a standard application database. Object or relational etc. does not matter.

Issue is ObjectScript.

So:

1) Can we develop, maintain and use an IRIS database and never use ObjectScript i.e. use only Java, Python, C++ interfaces etc. (exactly which one does not matter)? Would that make designing and using the IRIS database more prone to inefficiency and error?

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Hello community,

is there anything special to consider when running a foundation production regarding purge jobs (Ens.Util.Tasks.Purge)? I am thinking specifically of the QuickStreams, which according to my information are stored in a temporary database until the system is restarted. Since a system reboot is much less frequent then the purges, I wonder what happens to the QuickStreams whose messages and headers have already been purged. Is there a way to view Quickstreams (not content, but rather metadata) e.g. via the Management Portal?

Thanks for your comments and hints,

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Hi Developers!

Here're the technology bonuses for the InterSystems Multi-Model Contest that will give you extra points in the voting:

  • InterSystems Globals (key-value)
  • InterSystems SQL
  • InterSystems Objects
  • Your data model
  • ZPM Package deployment
  • Docker container usage

See the details below.<--break->

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Process-private Globals can be used as a data global in storage definition. That way, each process can have its own objects for the class with ppg storage. For example lets define a pool, which can:

  • add elements to a pool (ignoring duplicates)
  • check if an element exists in the pool

Here's the class:

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Article
· Feb 15, 2021 17m read
Four Database APIs

A concurrent session in IRIS:
SQL, Objects, REST, and GraphQL

Kazimir Malevich, "Athletes" (1932)

"But of course you don't understand! How can a person who has always traveled in a horse-drawn carriage understand the feelings and impressions of the express traveler or the pilot in the air?"

Kazimir Malevich (1916)

Introduction

We’ve already addressed the topic of why object/type representation is superior to SQL for implementing subject area models. And those conclusions and facts are as true now as they have ever been. So why should we take a step back and discuss technologies that drag abstractions back to the global level, where they had been in the pre-object and pre-type era? Why should we encourage the use of spaghetti code, which results in bugs that are hard to track down, and which relies only on virtuoso developer skills?

There are several arguments in favor of transmitting data via SQL/REST/GraphQL-based APIs as opposed to representing them as types/objects:

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Hi,

I have two namespaces

  1. In the first one, I have defined a class which Extends (%Persistent, Ens.Util.MessageBodyMethods), we'll call it NSOne.Msg.Req
  2. In the second namespace NSTwo, I want to use the previous class with something like SET pInput = ##class(NSOne.Msg.Req).%New()

I mapped the NSOne.Msg.Req package in namespace NSOne. In Atelier, I can see NSOne.Msg.Req in my NSOne. But, when I try to execute line 2 above, it tells me :

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Hi Developers!

Here're the technology bonuses for the InterSystems IRIS Globals Contest 2022 that will give you extra points in the voting:

  • Data-model implementation - 5
  • Functional index implementation - 5
  • Data Move usage - 3
  • Embedded Python - 4
  • Docker container usage - 2
  • ZPM Package deployment - 2
  • Online Demo - 2
  • First Article on Developer Community - 2
  • Second Article On DC - 1
  • Code Quality pass - 1
  • Video on YouTube - 3

See the details below.<--break->

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In this article I'd like to share with you a phenomena that is best you avoid - something you should be aware of when designing your data model (or building your Business Processes) in Caché or in Ensemble (or older HealthShare Health Connect Ensemble-based versions).

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Question
· Mar 13, 2018
DICOM to HL7

We have a case where a vendor can send us more information in the DICOM message rather than in the HL7 result message. In theory it should be possible to take a DICOM and convert it to HL7, stupid question is has anyone done it before? Does anyone have any good examples of a DTL they did to show me how to setup the message structures and translation?

Thanks

Scott Roth

The Ohio State University Wexner Medical Center

Scott.Roth@osumc.edu

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