· Sep 12, 2019
Features of *ENSTEMP

ENSTEMP was addressed already some time ago;
Article: Preventing Globals From Getting Journaled (Continued from How do I Minimize My Journals)

and is also in public documentation
Where InterSystems IRIS Stores Temporary Production Data

Though I'd like to understand if this is just naming a non-journaled DB
or are there also typical features of CACHETEMP / IRISTEMP related to it:

  • automatic clean-up at system startup
  • keeping Global Buffers in memory as long as possible
  • late writing to the storage file

In other words is it a 2nd, 3rd, .. fully feature blown IRISTEMP ?

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IRIS offers Durable %SYS Directory as a highly useful feature for working with containers.

Before inventing the wheel once more I'd like to know if a similar feature also exists for Caché / Ensemble.
Official documentation is quite silent about.
Though I have some names in mind that might know more about ( @Luca Ravazzolo ? @Dmitry Maslennikov ? @Eduard Lebedyuk ? )

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· Jun 10, 2019 1m read
more usefull Object Dump

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.

This small helper class allows you to dump an object to terminal or
e.g in background to some stream for later review.
By default, you see just properties with content,

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· Jun 5, 2019 1m read
Using Interjob Communication (IJC)

Earlier I've written about command pipes.
This is the internal variant of a PIPE.

To make this more tangible and visible for you I prepared a small example
The scenario is to run a monitoring process that receives
input from an unknown number of sensors. (Could be Lab equipment or similar.)

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· May 30, 2019 2m read
BackgroundJobs over ECP

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

Sure there are enough other ways to start a remote job, but the special
combination with ECP where the application server starts a process on a
data server without additional networking is worth to be remembered.

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· May 29, 2019 1m read
Simple Remote Server Control

This example is extracted from a long-running installation.
The purpose is to have 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 example shows a basic skeleton that might be easily filled by your real needs.

It consists of 3 sections:

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· Feb 8, 2019 2m read
Client Websockets based CSP

The Caché / Ensemble standard distribution contains in namespace SAMPLES
a nice example of a CSP page consuming WebService as a Client.
I have modified it not only to display the replies but to feed them back into a Global.
I used the classic Hyperevent to achieve this. The replies end up as a log in global^WSREPLY.
When there is no input anymore the page closes and goes away.

There are 2 versions with visible and hidden display during operation.
dc.WSCSP.reverseVerbose.cls and dc.WSCSP.reverseHidden.cls

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· Feb 8, 2019 2m read
Client Websockets based on Node.js

It will demonstrate the wide range that is openend by making use
of the power embedded in Node.js and its adapter to Caché, Ensemble, Health,..*
Node / JavaScript have wide reputation to work as a WebSocket client.
By using the Caché adapter it becomes easy to control it and to consume the results as a
Client for WebSocket Servers and to collect the replies in Caché, Ensemble, ..

I used node-v6.16.0-x64.msi and cache610.node as cache.node

You provide a Global for input:

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*** archived ***

The question has come up several times and I saw mixed answers and no quick example

My personal preference is using CPIPE device as you get back exactly the output you will get at the command line interface of your OS .
The tricky thing is to stop reading in time.
The example just displays what you normally see in your console.
it becomes useful if you look for things that you can't get from any $system.whatever()

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· Feb 27, 2018 2m read
Dataset Lightweight M:N

This data set demonstrates a basic M:N relationship between 2 tables
The dataset is targeted to show a slim implementation of M:N
It's no question that other implementations exist. But at significantly more storage consumption.

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· Feb 26, 2018 2m read
M:N Relationship

If you have worked with Caché Objects,
You know already all about Relationships (one:many , parent:child) ...
But you will not find a word on many:many relationships in the docs.

But I met the question quite often from new adopters of Caché objects:
"Is it possible to implement many:many relationships ?" YES - of course !

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· Feb 16, 2018 2m read
Adopted Bitmap

The base class Bmap.Person defines persons within an organization distributed
by various countries. All records are indexed by (Country, PersonalId).
this structure doesn't allow use of bitmaps.

So a wrapper class Bmap.PersonQ around the data eliminates the top level of
the index (Country) and isolates the PersonalId (%Integer, MINVAL=1).
We are ready to use a Bitmap index.

A few performance figures on 300010 generated records.
You see that Relative Cost are sometimes quite misleading.


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You probably have a similar experience.
The more I use Atelier the more I miss INSPECTOR that I had in Studio!

First for PROPERTIES that can inherit a variable number of Parameters beyond imagination.
take %XML.Adapter as the most obvious.
Where to find all inherited methods that I eventually want to overload? Take %Persistent as example.

Or where or how can %OnBeforeAddToSaveSet() (the correct camel case) be overloaded ?

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· Nov 11, 2017 3m read
Summary on Local Variable Scoping

This should be an overview over a subject that pops up over several places in online documentation mostly as remarks and never as dedicated chapter.

Once upon a time ... No it's not a fairy tale.
In the beginning of Caché (and before) you had your partition to run your code. Part of that partition was a space with all your local variables nicely sorted by %,A,..Z,a,...z

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