Opf3 Forum: General Discussion

Opf3 and ADO.net, Pervasive

Fri, 5 Jun 2009 1:27:52 PM GMT

I am using Visual Studio 2008 and Pervasive DB. I am getting an exception that says 'reached the maximum number of connection pools'. I dig about in some forums and it seems the problem is realted to ADO.net 2. Version 3 is supposed to take care of this.
First, I would like to know what version of ADO.net is using Opf3.
Second, I have installed the PervasiveSQL-SDK-ADO.NET-9.50 and also the Pervasive client and I would like to know which version of Pervasive Opf3 is using.

Thanks in advance!

OPF3 - Product Roadmap for 2009

Mon, 4 May 2009 7:40:06 PM GMT

Christian,

I noticed a dearth of announcements regarding future functionality for OPF3 and
I was wondering if you could share with us, your customers, where you see the product going over the course of 2009.

The reason I ask is that I know you were doing an internship with Microsoft at one point and it seemed to me that your own personal ambitions lay in the direction of joining Microsoft as a fulltime engineer. Naturally I was concerned about the impact that would have on OPF3 as a stand alone product offering.

Thanks again for an excellent piece of software, Christian,

IEnumerable to objectset

Wed, 18 Mar 2009 4:49:30 PM GMT

What's the best way to turn a Generic IEnumerable collection back into an objectset?
I have a temporary session objectset that has values removed/added and I wanted to use Linq to quickly remove unwanted entries. Here's the line that I need help on.

tmpObjectSet = tmpObjectSet .Where(p => permissionIds.Contains(p.PermissionId));

Thanks in advance.

Linq queries

Fri, 27 Feb 2009 4:31:07 PM GMT

I've got two main questions. First: Why don't these forms have a search feature, or wiki? Second: How can I return a standard non-enumerable array from a single column using linq? The scenario is that I need an decimal array of measurements from my object.

Here's what I've come up with so far

decimal[] SieveEntrySpecifications = ( from x in _context.GetPersistents() where x.MaterialId == MaterialId select x.MeasurementSpecification ).ToArray();

but I'm thrown a Cannot create mapping for type 'System.Decimal' without persistent attribute. exception.

Any ideas?

Thanks in advance.

How can I get Max(), Min() value using objectSet or GetObject<>

Thu, 5 Feb 2009 10:43:26 PM GMT

Hi,

How can I get something like this "Select max(field) from table" in opf getobject or getobjectset ?

does it have like this _context.GetObjectSet().Max(field) ?

thanks in advance.

Linq and Outer joins

Tue, 27 Jan 2009 10:42:32 PM GMT

Any time frame on when this will be supported? It would be a nice addition I think (plus of course I need it in a project!)

Modifying data as it is retrieved from the database

Fri, 16 Jan 2009 8:16:13 PM GMT

The database I'm working with is populated by a system that likes to pad strings. Generally, a string field is padded on the end with spaces to 72 characters. This creates convoluted XHTML when I output these strings from the database. I know I can create a user-defined type that will trim the strings, but to keep things simple, I'd really like to stick with the normal String class for string fields.

Is there some way that I can catch string field data as it is retrieved from the database and trim it before creating the persistent object?

Read only ID field

Fri, 9 Jan 2009 12:03:18 AM GMT

Hello,
I used the Wizard to generate my persistent objects and the ID field has a private setter:
[Field("customer_id", AllowDBNull = false, Identifier = true, AutoNumber = true)]
public int CustomerID
{
get
{
return _customerID;
}
private set
{
_customerID = value;

OnRowChanged("CustomerID");
}
}
When I attempt to instantiate the class, I get the following exception:
"System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.InvalidOperationException: Unable to generate a temporary class (result=1).
error CS0200: Property or indexer 'ClassName.Customer.CustomerID' cannot be assigned to -- it is read only"
If I remove the private designation from the setter, I no longer get the exception, however when I persist the object in the database, I get an inserted row with a new ID instead of an update.

problem with timestamp concurrency manager

Thu, 25 Dec 2008 10:22:29 PM GMT

Hello Christiaen,

I seem to have a problem when I try to use the timestamp concurrency manager.

When I do some debugging, it looks to me as there is a problem to find the property that is marked with the [TimeStamp] attribute.

Can I find somewhere a full sample that shows me how to use it ? I've tried to set it as it was told in the help file. Maybe I overlooked something.

Thank you for your help.

Regards

Ivo

Isolate OPF3 from the GUI

Thu, 11 Dec 2008 10:25:53 AM GMT

Hello Christian

I’ve read an post on the internet where you talk about ObjectSetHolder versus ObjectListHolder (Channel9, aug 2006).

Quote:
The way with IList, as you mention here, is also possible when using the ObjectSetHolder - I do that a lot, because i don't want any reference to Opf3 in my UI layers.

My question is : how do you use ObjectSetHolder without reference OPF3 on the GUI?
This is exactly my problem, I want to isolate OPF3 within the service-layer.
Do you have sample code?

Thank in advance

Greeting
Peter

ORM Comparison

Fri, 28 Nov 2008 12:25:50 PM GMT

Christian,
A blog is trying to do a comparison of ORM tools, you might put opf3 out there as it is certainly better than what they are showing now.

http://dnagir.blogspot.com/2008/11/orm-requirements-analysis.html

Al

CSLA.NET & opf3

Thu, 25 Sep 2008 3:20:57 PM GMT

Hello,

Is there anyone reading this post who knows more about CSLA.NET working against a Opf3 datalayer? Or just Opf3 in an CSLA application.

Anything

Greetings,
Raymond de Jong

ISelfContainedObject and dynamic configuration questions

Mon, 25 Aug 2008 1:14:53 PM GMT

Hi , i have following questions:

A: I want to implement custom object tracking.

I understand from the documentation how to mark my object as modified, but i want to control EXACTLY what fields are persisted to the datastore. I want to persiste only the
modified fields.

Is this possible?

B: Is it possible to configure the persistence programmatically, without attributes?
I want to be able to persist POCO object that i do not own, defined in other binaries.

Thank you

Identity Map question

Tue, 19 Aug 2008 12:36:56 AM GMT

Below is a snippet of a simple test I did to use the new IdentityMap feature, which isn't working for me - although it's highly possible it's user error!

//Code to create context removed....(regulare context w/ md5 concurrency....

  //Since it's not enabled by default
  context.IdentityMap.Enabled = true;

//Get every widget with an id greater than 1
ObjectSet widgets = context.GetObjectSet("ID>{0}",1);

//Get the first widget which will require a trip to the database.
Widget w1 = context.GetObject("ID={0}",1);

//Get another instance of the first widget which should not have to be retrieved
//from the database since it's in memory now.
Widget w2 = context.GetObject("ID={0}",1);

So when I look in the sql profiler I expect 2 calls to the db. One for the Objectset with the greater than. The second for w1. I am still getting a call to the db for w2 however even though it should be in the IdentityMap shouldn't it?

sqlite on new version

Mon, 18 Aug 2008 1:38:18 AM GMT

When trying to use the new sqlite provider and I get the following error:

"Unable to load DLL 'sqlite3': The specified module could not be found. (Exception from HRESULT: 0x8007007E)"

I built the project successfully after adding the .Net Sqlite provider.

On a side note, it's great to see the LINQ updates.

-Al