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:
I'd like to make you aware of a trap I just fell into.
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()
e.g.
- your servers IP address or addresses depending on your configuration.
- pinging any other server to see if it is still visible on the network
- running nslookup
In a single server environment, it is rather easy to create a transaction consistent backup.
Simplified:
You find (or force a specific point in time with no open transactions.
Freeze your server, take a snapshot and you are done.
I'm facing a specific sort problem.
There are several thousands of articles sold all over.
Users expect to get a description in local language sorted by their specific collation.
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.
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 !
HowTo depends on the related tasks: There is a heavy and a lightweight solution.
Both have in common that they are not just out of the box and you have
to add some code to manage it.
Let's take an example based on SAMPLES namespace:
we have the case of an N:1 relationship
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.
base
select count(*) from Bmap.Person
300010 global references 1600446 lines executed
demo 1
This a spin of from For and If with one line: to brace or not to brace
Has anyone seen or heard of a Beautifier for Object Script?
There is a bunch of them out for XML, HTML, JavaScript, CSS, PHP, .... https://codebeautify.org/
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.
next:
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 ?
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
As I mentioned in an early post the roots of COS were laid in the late 60ies of the 20th century.
Close to that time, BLISS was designed at Carnegie-Mellon University (January 15, 1970)
https://en.wikipedia.org/wiki/BLISS
Similarly in 1972 C language was written at Bell Labs.
https://www.bell-labs.com/usr/dmr/www/chist.html
Both were designed to overcome the portability limits of code written in assembly language.
While BLISS was running on DEC machines and vanished with Digital Equipment Corporation
C language and later C++ expanded on almost any processor technology until today.
As IRIS was announced yesterday by Paul Grabscheid I would be highly interested to get in touch with it.
- How can we get qualified for a closer view ?
- Where can we get some (preliminary) description + documentation.
- Is there any FT available ?
I'm especially interested in the areas around included/embedded/attached JVM and SPARK .
This is a rather personal view of the history before Caché.
It is in no sense meant to compete with the excellent books from Mike Kadow discussed in an earlier article.
We have different histories and so this is meant to create a different perspective of the past.
The whole story started in 1966 at MGH (Mass.General Hospital) on a PDP-7 Ser.#103
with 8K of memory (18-bit words) [today = 18K byte ] as a spare system.
I worked through the Community for proposals to provide end users
in an easy way with data formatted as EXCEL sheet.
There is a great article Tips & Tricks - SQL to Excel
there's an important message embedded: "EXCEL can interpret HTML tables and display them as usual"
Where's the light weight export to EXCEL ?
Good old CSP is well equipped to produce HTML tables accepted from EXCEL as input.
With modern Browsers you don't even need <head>and <body> tags.
So the required code around your SQL result set is really slim.
And you are free to add any formatting you need either by HTML or in SQL.
DC is still a hidden jewel for customers:
the useful content is in the replies
showing the use of $SYSTEM.OBJ.ValidateIndices()
It's a general problem that feedback from users is often quite poor.
Sorry,
the original announcement page is not reachable or deleted.
In a previous exercise, I was able to show the power of Caché.
A medium-designed set of interdependent tables with some GB of data.
URLs cross reference over some million pages resulting in ~3 billion records
Competition was between
Criteria were Speed + Storage consumption
I composed a customized loader fed over a "raw" TCP connection
Mapping the "objects" into the final table by directly writing to Global Storage.,
GIS stands for Geographic Information System.
and it's not a typical arena for Caché. But it's definitely an environment with high data volume.
You see 3 major areas
- Visual front end:
A mature area well covered by a bunch of commercial and open source products.
No need for Caché there.
- GIS mathematics:
JTS (Java Topology Suite) is fixed standard that covers all requirements and can be linked to Caché by the Java Gateway
or the C, C++ incarnation of this standard library using Caché Call Out Gateway.
So far no added value by Caché.
Recently upper case ß was defined as an official character for German
how can this be adjusted in Caché 2017 ?