#Caché

I have seen a customer problem recently where the use of a virus scanner running over Caché databases was causing intermittent application slow downs and bad user response times.

This is a surprisingly common problem, so this short post is just a reminder to exclude key Caché components from your virus scanning.

Generally virus scanning must exclude the CACHE.DAT database files and Caché binaries. If an anti-virus is scanning CACHE.DATs and InterSystems files then system performance will be significantly impacted.

Development productivity? Isn’t it kind of an oxymoron? Anyhow, we all dream a magic tool which does the tedious job of the software development and leave the intuitive or creative part on the developer. Atelier is the next generation tool of InterSystems aiming to boost the productivity of Caché/ Ensemble based software development. Atelier is based on the popular Eclipse IDE platform, which makes available the “infinite” pool of third party tools for Caché developers. Those tools can truly boost the productivity. This short article gives some examples how third party plug-ins can help developing for Caché. It is an absolute beginner’s guide, beginner to Eclipse but experienced to Caché.

With the release of Cache 2016.1, JSON support was re-architected and made part of the core object model with the creation of %Object and %Array classes, which allow you to create dynamic JSON enabled objects and arrays.

On a recent demonstration I was working on, I had the need to create a REST web service that returned a JSON representation of a persistent object. After searching for methods that would allow me to accomplish this, ultimately I found none, until now.

Checking if Directory or File Exists:

Outlined below is an example of how to check if a directory exists:

Set directoryName="c:\temp\nosuchdir"

/* Check for existence of a directory - Return Value:  0 - directory does not exist;  1 - directory does exist  */

Set directoryExists=##class(%File).DirectoryExists(directoryName)

If ('directoryExists)  // do the processing for when a directory does not exist

Outlined below is an example of how to check if a file exists:

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?

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:

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.

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.

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.

NewBie's Corner Session 28 Various Methods to Traverse a Global

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

Judging from the number of responses to Session 27 Traversing A Global, developers are passionate about their methods. I am not here to judge the merit of the various methods.

Over the next few pages I will demonstrate a number of methods to Traverse a Global. If you don't already have a favorite they may help you pick one.

Interesting to see this latest ranking come to my attention:

http://db-engines.com/en/ranking/graph+dbms

Look what's ranked 16th. Shame a decision was made to deprecate it

To install the Python binding on Windows one must follow the instructions in the following:

https://blogs.msdn.microsoft.com/pythonengineering/2016/04/11/unable-to-...

The reason is that ActiveState Python version 2.7.X is built with Visual Studio 2008 and Microsoft provides Visual Studio 2008, which one must install, so that Python C extensions can be built.

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

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.