#Object Data Model

Class Queries in InterSystems IRIS (and Cache, Ensemble, HealthShare) is a useful tool that separates SQL queries from Object Script code. Basically, it works like this: suppose that you want to use the same SQL query with different arguments in several different places.In this case you can avoid code duplication by declaring the query body as a class query and then calling this query by name. This approach is also convenient for custom queries, in which the task of obtaining the next row is defined by a developer. Sounds interesting? Then read on!

I try to compare classic JOIN against implicit JOIN.

It is a simple case. But I am surprised.

Let's say we have two serial classes, one as a property of another:

Class test.Serial Extends %SerialObject
{
Property Serial2 As test.Serial2;
}

Class test.Serial2 Extends %SerialObject
{
Property Property As %String;
}

And a persistent class, that has a property of test.Serial type:

Class test.Persistent Extends %Persistent
{

Property Datatype As %String;

Property Serial As test.Serial;

}

So it's a serial, inside a serial, inside a persistent object.

Hi Community! I need your advice.

The method below is 6 times slower on production server than on developing machine:

This is a sample to use %JSON.Adaptor class available in IRIS to produce a snapshot of your object.

The sample consists of 2 classes that are variations of what was known in Caché/SAMPLES as Sample.Person.
Be aware that the possibilities are limited by %JSON.Adapter and how you make use of it.

Once in place, you create some test data by Populate().
You select an object and take a snapshot.
You apply changes to your object and take another snapshot.
And see the difference.

BINGO!

Hello community,

I recently started to work with Ensemble. I defined a subclass of EnsLib.HL7.Message. In my production I receive HL7v2 messages and transport them using the Message Router to a business operation. The operation class has an OnMessage method with parameter

pObject As MySubclassOfEnsLibHL7Message.

Introduction

The common requirement in many applications is logging of data changes in a database - which data has changed, who changed them and when (audit logging). There are many articles about this question and there are different approaches on how to do that in Caché.

What if you could serialize/deserialize objects in whatever format: JSON, XML, CSV,...; attending different criteria: export/import some properties and not others, transform values in this or that way before exporting/importing,...; and all of this without having to change the class definition? Wouldn't that be great??

Well, perhaps it's a goal too ambitious to reach 100% but, exploring this idea, I've developed a bunch of classes that I thought it was good to share. If you want to test, change, modify or improve the code, or just take a look at it, you can do it here. There you'll find a more detailed explanation (see Readme.md)

Is it possible to use a class parameter in class query?

Example:

Class SomeClass
{

Parameter SOMENAME = "Name1";

Query SomeQuery() As %SQLQuery
{
SELECT ID || ..#SOMENAME  || Name FROM Table
}

}

Hello community!

I have a question about the %OnSave method of a class. We have a class that has two properties that are classes.

Class A

Class B

Class C

Class A.PropertyB as Class B

ClassA.PropertyC as Class C

Classes B and C also need to point back to Class A - it's just the way it is. We need to be able to use any one of these classes and get to the others (it's actually even more complicated than this, as Classes B and C also have a PropertyC and PropertyB as well, respectively) :

I have several BPL's that act like SQL Server Integration Services (SSIS) where they are transferring data. When I do this they are all being written under 1 session id, is it possible to make the BPL create multiple session ID's as it is cycling through a Snapshot, so it is easier to read in the trace?

Thanks

Scott Roth

The Management Portal allows you to Export one or more globals to a file that you can then Import into that or another namespace. However, the Management Portal can only be used to export entire globals. For exporting selected nodes or subtrees within a global, a different utility is necessary. This utility is the Export() classmethod in the %Library.Global class, which can export an entire global but also has the ability to export selected nodes or subtrees.

I am still working on a generic task where I need to apply journal file records to another database. Initially I didn't want to use Journal.Restore class methods as I need to perform some data transformation, and it seemed that the clearest way to achieve it was to read journal file record by record using %SYS.Journal.Record API.

Hello!

My goal is to serve files using REST classes only (no filesystem should be used), and I am a halfway far from it.

What I am succeeded in, is serving character files (html/css/javascript/etc) using the next approach: