#Globals

I would like to introduce my new project for the Globals Contest. A very new view for the globals browser

NewBie's Corner Session 27 Traversing A Global with $Order Part 1

Welcome to NewBie's Corner, a weekly or biweekly post covering basic Caché Material.

Traversing A Global

Perhaps the most difficult concept in Caché/MUMPS is its Global Structure. This session and several that follow it deals with the Global Structure. However, just presenting the material will not guarantee your understanding of it. You must experiment with the data and concepts that are presented.

I have a simple app which tries to establish a connection with a Cache database instance via Global API for Java:

import com.intersys.globals.Connection;
import com.intersys.globals.ConnectionContext;

public class Assignment {

    public static void main(String[] args) {
        Connection connection = ConnectionContext.getConnection();
        connection.connect("SAMPLES", "_SYSTEM", "SYS");
    }

}

The expection I am getting:

Suppose we need to store millions of values temporarily, that means, we don't care about them if we lose them but our application use them to get realtime information. Should I use Cachetemp or whatever other DB without journaling enabled? If answer is Cachetemp, shouldn't be a problem if we decide to scale using App Server + ECP? I'm not sure what would happen with the app logic in such architecture as I guess I couldn't map and share cachetemp...

Any idea/suggestion?

Globals in Caché / Ensemble / IRIS are normally invisible over SQL access
This example shows how to overcome this limit.

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.

Hi,

I have a class with around 400k lines and 60 columns. Class storage is Cache SQL storage (Mapped from a global).

I want to create multiple indices on certain fields.

I am familiar with two approaches:

1. Create a new map (Index type) on a pointer global.

2. Create a bitmap index

Which approach is more recommended to be used in the case I described? If there are any other approaches, I will be happy to hear.

Thanks :)

Hi,

Most of my classes are mapped from Globals. I want to access Cache classes from a BI software through ODBC connection.

'Last update' information does not exist in most of the classes. My question is whether there is a 'last update' timestamp that is automatically generated for each line in classes I can extract to external systems?

Thanks

We are trying to create a simple class extending %RegisteredObject that could be used as a singleton. However we are not able to store it in a global to later be retrieved (by the same process but elsewhere in the code).

I resumed my issue in this small code sample :

We're developing Ensemble PoC and one day our frontend developer (who doesn't have Ensemble production running) said that Populate just doesn't cut it and he needs to see the real data. He needed only one object, but the problem was - it's a big object. Still, I checked ids of everything related and wrote this command (parts omitted, but you get the idea):

What is the best way to get the size and other storage details of individual Globals in a namespace?

Thanks,

Mary

Have very little XML experience and have been able to manually create output. Have a need to take data that I store in a M global (example: ^TML("HDATA", ) and out put it in CCDA XML format.

Are there any examples of M code using the XMLWriter to accomplish this?

Or can anyone provide some guidance

Any help would be greatly appreciated.

Let's say I have a global named ^a and I need to export its nodes 1, 2, 3, 5 only.

Currently I write something like this:

Write $SYSTEM.OBJ.Export("a(1).gbl,a(2).gbl,a(3).gbl,a(5).gbl", "C:\Users\eduard\Desktop\a.xml")

Is there a way to write it shorter? I want to write global node once and list all the subscripts I need.

A More Industrial-Looking Global Storage Scheme

In the first article in this series, we looked at the entity–attribute–value (EAV) model in relational databases, and took a look at the pros and cons of storing those entities, attributes and values in tables. We learned that, despite the benefits of this approach in terms of flexibility, there are some real disadvantages, in particular a basic mismatch between the logical structure of the data and its physical storage, which causes various difficulties.