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#Caché

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

Documentation.

Is it just me or is the sync mechanism way too slow and too trigger happy to be used for large projects? It keeps "Caching for server connection" which takes a good five minutes!

Has it been tested with a large number of classes and CPSs? I have about 2000 of each.

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I've been wondering about some code that I have come across a lot over the years.

Let's assume I have class Cinema and class Film.
Conceptually the data in these classes are never really physically deleted but only flagged as such, due to business requirements.

What I find is that developers tend to create a 3rd class "CinemaFilms", in a child relationship to parent Cinema, with a reference to Film. Rather than a one-to-many between Cinema and Film.

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Let's say I have this property:

Property FavoriteColors As List Of %String;

I heed to convert it to JSON using SQL or at least without object access (so direct global access).

What's the fastest way to do that?

I thought about JSON_ARRAY and JSON_ARRAYAGG sql functions but they don't do that.

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Recently, a partner company started to develop an Angular client for their Cache application. Together, we decided to leverage the power of Caché dynamic objects to exchange JSON encoded data between client and server parts. However, we realized that currently there is a gap in Cache JSON implementation that prevents simple use of traditional registered and persistent classes to exposed their data with the same ease as with XML. I wrote a small JSON adapter, that does the job and bridgers the gap. It's purpose is simple expose data described by a regular Cache class in a one-to-one fashion to a %DynamicObject. On the other hand, when a serialized JSON data comes in, it can be easily deserialized into dynamic object and subsequently bound to regular class by the newly created adapter.

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Hi All,

I need urgent help,

I want to export the values from Global to CSV file.

Values are in global are :

^Global1(1)="1,2,3,4"
^Global1(2)="5,6,7,8"
.
.
.
^Global1(n)="n,n,n,n"

I want output in CSV File as:
1,2,3,4
5,6,7,8
.
.
.
n,n,n,n

I made a class:

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Article
· Nov 23, 2017 12m read
Where is my global stored?

It's well-known that namespace global mapping helps us to write code independent on database storage details (Caché instance name, directory path). But sometimes we can face problems accessing an unsubscripted global which has subscript level mapping (SLM) defined. Most of such cases are evident and associated with administrative tasks that should be done on database level, but some of them can confuse even an experienced developer. Just to start:

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or "Bonus Breakage"

In our last lesson, we added a relationship between 2 persistent classes. We are clearly going to need to start creating REST Services to expose CRUD operations for each of these classes, but before we do that, we should really finish defining our linkages. We added code to our Widget toJSON to spool off related Accessory data, so we should really do the reciprocal and allow Accessories to return all Widgets that are compatible.

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Question
· Aug 16, 2017
PROTECT error

I try to run below two statements

Set tRS = ##class(%ResultSet).%New("%Dictionary.ClassDefinition:SubclassOf")
​set tSC = tRS.Execute("%Persistent")

and I always get <PROTECT>check+5^%Dictionary.ClassDefinitionQuery.1

The login user is _SYSTEM and should have all the permissions.

I cannot run queries in the $SYSTEM.SQL.Shell(). I would get <PROTECT>%GenerateMetadata+16^%SQL.StatementMetadata.1

However, when I run the query through SMP, everything is fine.

Any idea where could I start to investigate ?

Thanks.

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or "Didn't you say you would cover Persistent Objects in Part 5, Chris?"

Yes, that was the plan. This is a pretty important topic, so it get's its own Article

Up until now, we've display widget JSON that has been created by a basic loop. Clearly this isn't of much value. Now we have our stack connected together, and we can see that the data is flowing to the Welcome page, it's time to complete the stack and start feeding our service from "real" data.

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Question
· Nov 16, 2017
Caché service does not start

Help, after a day of coding, I wanted to backup my files. I found out that alle of my 3 instances of caché refuse to start.

the error says: cstart-exe-fout (112 Service for Caché instance did not start).

Is there a way to solve this? (off course the management portal does not work either.)

I think there has been a power interruption as the battery from my laptop does not work, and the power went off before

shutdown.

Thanks in advance!

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Hello; we have users on the system with cache logins. They have access to a specific namespace, and no access to %SYS of course. I'd like to give each user the ability to change his own password from within our application, using Security.User.PasswordExternal. This only exists in the %SYS namespace, and the average user can't get to it.

Should I give the users access to this column in this table (column Password, table Security.Users)? What about access to the namespace? Is this possible? Has anyone done this before?

Thanks,

Laura

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Apache Spark has rapidly become one of the most exciting technologies for big data analytics and machine learning. Spark is a general data processing engine created for use in clustered computing environments. Its heart is the Resilient Distributed Dataset (RDD) which represents a distributed, fault tolerant, collection of data that can be operated on in parallel across the nodes of a cluster. Spark is implemented using a combination of Java and Scala and so comes as a library that can run on any JVM.

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