Both running VMs and containers allow multiple processes inside. I'm not asking you for a deep dive, but can you explain if the mechanism that allows this is the same or similar between VMs and containers, or if they use completely different mechanisms.
I would do it this way to avoid Else:
Open <some device>:"R":0 If '$test { Write "could not open device" Quit }
Danny and Robert, of course I understand what you are saying (we are the same generation!). Also, I am not trying to be the Developer Community police.
In posts that are asking "what's the recommended way to do this?" we should answer that question. There's no point in mentioning old syntax in that context. Saying "don't do this, but you might see it someday" helps the subset of people that might work with old code, but doesn't help and may confuse the people that are working with new code. It doesn't belong.
On the other hand, if there's a post asking "what are some older/confusing syntaxes I might encounter when working with M or ObjectScript?" we should answer that question. We all have examples of that.
C'mon, let's stop mentioning old features like argumentless Do and legacy ELSE
There's just no point in doing so.
The legacy versions of If and For commands don't use curly braces. But there are no legacy versions of While and Do/While, which require curly braces. So rather than trying to remember which commands use or don't use curly braces, just use curly braces all the time for these, as well as Try/Catch.
Regarding post-conditionals, it's a good habit to put parentheses around the condition, which allows you to put spaces in the condition.
This is valid syntax: set:a=4 y=10
This is valid syntax and more readable: set:(a = 4) y = 10
This is invalid syntax: set:a = 4 y = 10
Slightly improved syntax would be something like this:
if ($zdh(date1,8)<$zdh(value,8)) && ($zdh(value,8)<$zdh(date2,8)) { return 1 }
else { return 0 }
Setting Startup Namespace in the User definition affects Terminal logins. The feature was expanded to affect the Portal in v2014.1
No. I have a feeling that some versions of M that ran on VMS added the $, and some versions of M that ran on UNIX added the !. So we support both.
And don't forget about using ! or $ to load the interactive sub-shell.
It's like using $zf(-1). You can do !pwd or $dir, for example.
I haven't seen this crash at all. Is it possible to share more details about the crash? Error message, for example. Also, if the last edited routine is locked, that doesn't require a restart of Caché. You can find the entry for the routine in the Lock Table (in System Operations) and delete it.
Regarding the user for Caché/Ensemble processes, the user for those is not always the user that starts/stops Caché/Ensemble. My instance of Ensemble runs on the Mac. For several years, I do a custom install so that I can change the answer to the 4th question below from cacheusr to joelsolon.
User who owns instance: joelsolon
Group allowed to start and stop instance: staff
Effective group for Ensemble processes: cacheusr
Effective user for Ensemble SuperServer: joelsolon
All the Ensemble processes run as OS user joelsolon because of this.
I don't actually have an answer to your question, but maybe these points will help.
One clarification that might help you: the "Ensemble Controller" Service is not an Ensemble process, so the user assigned to that Service doesn't affect what you're asking about. The "Caché/Ensemble Controller" Service is simply something that allows you to start/stop the local Caché or Ensemble. It's just like start/stop on the Launcher (the cube or the E).
It is possible to programmatically add a relationship to two persistent class definitions at runtime, and then compile those classes. That gives you the same result you'd get if you had added the relationship to the class definitions at design time. So I don't think that's what you want.
The term "Relationship" as defined in Caché means "objects of these classes can be linked at runtime, and this relationship will be stored when the objects are saved." So your need to create relationships between persistent objects "as and when they're required" doesn't really match up with this definition. Either a persistent class is in a relationship with another persistent class, or it isn't. It's not possible to have some objects of the class without the relationship definition, and other objects of the class with the relationship definition.
Maybe you just need to substitute one-many relationships for all of your parent-children relationships. One-many relationships are independent; the relationship is not required like it is in parent-children relationships. In v2013.1 and later, you can set the OnDelete action of the one-many relationship to "Cascade" so you get delete behavior similar to parent-children.
Files are now also here: https://github.com/joelsolon/DevCommunity/tree/master/AppMon
Does this work with character streams also?
Here is some information about debugging CSP pages using Studio. I actually just taught this to students in class yesterday!
1. You can't set a breakpoint inside the ObjectScript on a CSP page (inside a <script> tag). But the workaround for this is to use the View > View Other Code and load the class definition that's generated from the CSP page. Then you can set breakpoints normally.
2. Once you've set breakpoints, you can set your CSP page as the Debugging Target, and launch it directly from Studio. The page runs in a special "debug mode". This means that the normal timeouts (typically 60 seconds) are suspended, so that the browser and the CSP Gateway will wait as long as necessary while you step through the code.
You can step through the code that is called when the page is first being built, and you can also step through code that is called via a hyperevent.
The only issue with stepping through the code is that Studio does not seem to be highlighting the current line as it normally does. I think this used to work fine, so I may bring this up with the developers. But a workaround for now is to use the "Call Stack" tab of the Watch Window. The top line of the call stack shows the label+offset of the current line. As you step, the top line is updated with the current label+offset. You can simply click the top line whenever you want and the Code Window will scroll to that line, also showing you the current values of the variables.
Option #1 is "store all persons together in the same global." So, people that are just regular persons, as well as presidents, senators, and representatives, are all stored together, with a single shared ID sequence. Optionally adding [Abstract] to the Person class prevents persons from being created/stored; there will be only presidents, senators, and representatives. With or without [Abstract], adding the bitmap extent index allows quick retrieval of different types of persons.
Option #2 is "store different types of persons in separate globals." Kyle's original description of how to do this is correct. Similar to using [Abstract] for option #1, optionally adding [NoExtent] for this option prevents persons from being stored. So the global structure you show in your first question is correct. Omitting [NoExtent] doesn't change that. You don't have to also use [Abstract] for option #2, but you can.
I thought IKnow required a special license. Can I really do all of this with my regular old Caché license?
In the process of writing this article, I discovered that our documentation on these two keywords contains the following sentence: "When you compile this class alone, the compiler does not cause the other classes to be compiled."
That sentence is incorrect. The documentation has now been fixed, and the updated information will be available online when we refresh the online content.
Another variation is where the USA.Person class is marked Abstract (so there are no objects/rows that are only Persons). For Kyle's Option #1, we'll make USA.President, USA.Senator, and USA.Representative subclasses of USA.Person. All the politicians will be stored together in the ^USA.PersonD global, with each type marked using the "~USA.President~"-style syntax. Without the bitmap extent index, finding all Senators requires looking through the entire global. With it, there is a bitmap index for each type of politician. Note that this variation provides 4 tables: Person (showing the common data for all politicians), and President, Senator, Representative (showing all the data for each type, including the Person data).
For Kyle's Option #2, the subclasses inherit from %Persistent and USA.Person, and each type of politician is stored separately from the other types. When doing this, you would normally specify [NoExtent] for the USA.Person class. There won't be a Person table in this case.
Usually the variable subscripts in a global will have a name of some kind, known to the developers that wrote or support the application. The name may also be known to the users of the application. I recommend using that name for the property, such as "EmpID" or "EmployeeID" rather than something generic like "Sub2".
If your class inherits properties from another class, substitute %compiledclass for %class in the solution above.
The default behavior for %Save() in Caché classes is still to use $Increment, which will be fine for many cases. $Sequence is intended for cases where the volume and speed of inserts is very very high.
Very good article that really shows the benefits of $sequence. Do you have an explanation for why the calls to LastName() and FirstName() went from 16.8 sec (using $increment) down to 8.2 sec (using $sequence)?
Also, there's a typo: "acquisitoin" should be "acquisition".
This is interesting stuff and it's good to revisit this as ObjectScript evolves. In the old days, there was advice about things like this:
But we always reminded people that these things could change from platform to platform, and that extra database references were usually much costlier than the differences between coding things one way vs another.
So, Tim, if you've got the time, please tell the Community if your tests show different values on Windows vs Linux vs Unix vs OS X. And (this might be harder), give us your opinion on a "tipping point" or a "when to care about this point"; that is, if the delimited or list string has fewer than N pieces/items, it really doesn't matter which method is used, but above N, use the $listlength method, and above M, use $listnext. Something like that.
I never updated this post with the workaround, sorry! The problem is with Secure Storage. You can reset it by going into Atelier > Preferences > General > Security > Secure Storage. Click the Contents tab. Under com.intersys.eclipse.connmgr, you'll see an entry for the connection to the Caché server. Delete that entry, and you should be able to recreate the server connection.
Spoke too soon. Trying to delete or edit a broken connection fails. I am reporting this.
Server Explorer exists on the Mac and was open. I had only used it to explore the contents of the server. But it also allows editing and deleting of the server connection itself. Thanks!
Also note that Caché developers will be able to choose to use Atelier even if the Caché server is not yet on v2016.2 or a later version. Steps:
Each developer can choose between familiarity with Studio and easy integration with the server (with perhaps no integration with source control), or familiarity with Eclipse and easy integration with source control (with an extra step or two to integrate with the Caché server).
Small comment: use $this instead of ##this, even though they compile to the same thing.