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#Caché

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InterSystems Caché is a multi-model DBMS and application server. See more details here.

Documentation.

Hi!

I believe the simplest is (to work with csv delimited by ";"):


set file = ##class(%File).%New( "data.csv" )
    set sc = file.Open( "R" ) 
    if $$$ISERR(sc) quit    ; or do smth

    while 'file.AtEnd {
        set str=file.ReadLine() 
        for i=1:1:$length( str, ";" ) {
            set id=$piece( str, ";" ,i ) 
            write !, id  // or do smth
        }
    }
    do file.Close()

Possible options:

different variants of error handling with sc code.

Embrace while loop into try/catch block.

And what's yours?

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Article
· Nov 8, 2016 4m read
Introduction to Outlier Selectivity

Beginning in Caché 2013.1, InterSystems introduced Outlier Selectivity to improve query plan selection involving fields with one atypical value.

In this article, I hope to use an example 'Projects' table to demonstrate what Outlier Selectivity is, how it helps SQL performance and a few considerations for writing queries.

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Hello,

This package may be of interest...

Link: https://github.com/litesolutions/cachedb-import

I have programmed this over a hunch, in order to facilitate the retrieval of source code from a Caché installation. It makes use of the Java API provided by Caché.

Right now, I use it as a means to salvage sources in order to analyze them using the SonarQube plugin I develop for my employer. Unfortunately this plugin is not open source.

I am calling for help here, on two fronts:

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I was recently troubleshooting a problem on a Linux (RHEL) instance of 2016.1 at a site. For policy reasons their sysadmins wanted to update the Caché installation so it used network accounts for its cacheusr and iscagent users and groups instead of the locally-created ones that had been set up during original install of Caché.

To do this they ran various commands including chown

Afterwards non-root users couldn't obtain a terminal session using the csession command. Instead they receive this message:

cache: Permission denied

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Article
· Mar 4, 2016 1m read
Getting my head around a class model

There's plenty of goodness in the %-packages InterSystems supplies, and it seems that every new version of Caché brings something new. The browser-based class documentation (a.k.a. Documatic) generally provides a good level of information, but on the basis that "a picture is worth a thousand words" I sometimes want a diagram.

For example, when trying to navigate the %Dictionary package for a project that needed to find out about class definitions, here's one of the UML class diagrams I created.

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Article
· Nov 11, 2016 2m read
Caché process failures on RHEL V7.2

Caché process failures on RHEL V7.2

InterSystems WRC has investigated several issues of process failure that can be attributed to a recent change in Red Hat Linux.

A new feature implemented in RHEL V7.2 (systemd-219-19.el7.x86_64) can cause O.S. IPC (Inter-process communication) semaphores to be deallocated when a non-system RHEL user logs out (system users, i.e. with a UID number < 1000, are excluded)

3 1
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Article
· Mar 6, 2016 2m read
Who does Windows think I am?

When my COS code is executing in a Caché process it might want to interact with the host operating system. For the purpose of this post I'm focusing on a Windows host, but much of it applies to other host OS platforms as well.

A common example of host OS interaction is when my process wants to read from or write to a file. What credentials will apply when Windows is checking whether or not to allow me access to the file?

To answer that we need to consider another question. How did our process start?

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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):

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C:\data\backup.bat :

C:\InterSystems\Ensemble\bin\cache -s"C:\InterSystems\Ensemble\Mgr" -U%%SYS ##Class(Backup.General).ExternalFreeze() <C:\data\login.scr

echo %ERRORLEVEL%

rem note that we need to check errorlevel from highest to lowest here....

if errorlevel 5 goto OK

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Article
· Apr 4, 2016 1m read
2015.2.3 Maintenance Release

I am pleased to announce that Caché and Ensemble 2015.2.3 are now available as maintenance releases.
For a complete list of the corrections in 2015.2.3, please review the release notes.

Caché and Ensemble 2015.2.3 are available now for the same platforms as 2015.2.2

The complete set of supported platforms, including specific point releases and/or patches, is detailed in the Supported Platforms document.

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The MONITOR process (also called the Caché Monitor) scans the messages in your cconsole.log file and sends you emails based on the severity of those messages. The MONITOR is configured using the ^MONMGR utility in terminal.

The MONITOR should not be confused with the similarly named System Monitor, which checks a variety of system health and performance metrics and can log messages regarding them to the cconsole.log, where they can then be scanned by the MONITOR.

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You may have missed the news that support for older version of Internet Explorer ends next week Tuesday, January 12th. The original blog post from Microsoft can be found here:

https://www.microsoft.com/en-us/WindowsForBusiness/End-of-IE-support

A patch will go live next week Tuesday, that will nag users of older IE versions to upgrade to a recent version. The patch is identified as KB3123303. You can find more information about this patch here:

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Article
· Feb 25, 2016 2m read
Alert: Incorrect SQL Results

February 25, 2016 – Alert: Incorrect SQL Results
InterSystems has corrected a defect that can cause incorrect results for certain SQL INSERT, UPDATE, and DELETE statements.

This defect is present only in Caché and Ensemble 2015.2 and HealthShare distributions based on them. The problem affects all platforms.

Incorrect results occur only when two or more of these statements are nested within each other.

The example below demonstrates one possible way for this problem to happen:

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Hi,

I'm posting this for the benefit of others. Not often one changes certificates in Cache, at least in my case. I run a system, that uses certificates to encrypt SOAP messages, and since the last time I ran it, my certificates expired.

So I renewed them using our PKI tool, so far so good. I gave all (3) certificates the same names (and filenames too) as to those expired, thinking that everything would just work fine next time I call the SOAP service.

Unfortunately, I got trapped.

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Article
· Jan 12, 2016 9m read
DecisionTree 
Is there someone that has developped a program in order to create a 
"decisiontree"? Depending The answer to a question leads to another question, and so on, 
and so on, and there is an option to return to another point in the decisiontree.

Best regards,

Simon.

p.s. I've already got something, but it's not workable. But to get an idea:

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Today I'm releasing a new EWD 3 module - ewd-feder8.

ewd-feder8 is a federation or integration platform, built as an extension of the EWD 3 ewd-xpress module. So what does it do and what's it for?

It's all about federating and integrating multiple web or REST service end-points.

At its simplest you can use it as a proxy server in front of a remote web service or REST end-point.

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If I have defined a class query in one of my classes and I want to use that query from a method of another class, what are the pros and cons of using the %SQL.Statement interface versus the %Library.ResultSet interface?

I believe %SQL.Statement is the newer interface.

So if the old way is:

USER>s rs=##class(%Library.ResultSet).%New("%Library.File:FileSet")
 
USER>s sc=rs.Execute("c:\s\","*.txt")
 
USER>w sc
1
USER>while rs.%Next() {w !,rs.Data("Name")}

...

then the new way is:

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Article
· Oct 4, 2016 1m read
How to Parse a URL in Caché

How to parse a URL in Caché:

Let's pretend you are working on a project where you may be retrieving a URL for some purpose and you have the need to be easily able to parse apart that URL to get the various components that make up the URL.

Here's how to do that:

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Article
· May 13, 2016 1m read
mySQL data importer tool

Hi,

If you want to import data from a mySQL export file (exported with mysqldump), you will find here a little script that could help.

Only the INSERT commands in the sql file are executed into Caché. Indices are not computed for better performance.
%NOINDEX, %NOCHECK and %NOLOCK are generated on each INSERT line.

Currently, the file can not contain a "),(" pattern inside the values part of the INSERT command. If this is the case, the line is skipped. This feature may be implemented in the extractValuesList method.

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Article
· Dec 7, 2016 3m read
Enable CORS for CSP/ ZEN Applications

As web application gets more complex, more technologies are involved into the application development. Once it gets deployed in large scale the configuration gets more complex too. For sure one of the most difficult part of the story is the security. In a complex solution when independent servers are feeding single web pages with contents, it is indeed challenging to keep the integrity of such system. HTML5 introduced a (weak) security constraint, the Cross Origin Resource Sharing (CORS). This article tells how to enable CORS for CSP/ ZEN applications.

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NewBie's Corner Session 2 Variables Set and Write commands

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

Session 2 – Click on the Caché Cube in your system tray and select Terminal to try out the commands.

Variables

Like other computer programming languages, Caché uses Variables and the values they represent to control programming. Variables are elements that represent data values. Manipulating and interrogating variables is at the root of programming.

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RESTful API Call From Cache to Particle.io Electron

Tom Fitzgibbon | Multidata | 212-967-6700 x537 | tom@mul.com

Summary: Simple Blink Tutorial for Particle.io Electron Device from Cache

Electron device is a tiny ARM processor ($40-$60) that connects to Particle’s world wide leased 2G/3G network (about $3/mo) and runs off an included LiPo battery. Using Cache’s %Net.HttpRequest you can send/receive data, control hardware and read sensors.

Step by Step (about 1 hour)

1) Get the Electron from store.particle.io.

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