I'm trying to adapt the guide http://docs.orchardproject.net/Documentation/Creating-1-n-and-n-n-relations for creating an N-to-N relation in my Orchard module, but I get an exception "unable to cast NHibernate.Collection.Generic.PersistentGenericBag`1[ArealAds.Models.StreetAreaRecord] to System.Collections.Generic.List`1[ArealAds.Models.StreetAreaRecord]". I don't fully understand what's going on behind the scenes so it's hard for me to debug. What is the likely cause of this error? Where do I start looking?
You should change the type of the related item collection from List<T> to IList<T> (or more generic IEnumerable<T>), as NHibernate cannot map the property to it's internal item collection (which implements IList<T>).
See similar issue.
You did not correctly follow the guide. There is an example of an n-n relationship in the document and it works. Without seeing any of your code, it's hard to say what went wrong, but it has to be different from the tutorial somehow. Another example you can look at is the bundle part in this module: https://bitbucket.org/bleroy/nwazet.commerce. it establishes a n-n relationship between content items.
Related
I'm trying to add new record to my DB, but I got this error:
This is my schema.rb:
And this is my method create:
And this is my form to add a new record:
The param is sending correctly, but when I click on Upload button, nothing is happen, and if I try to add the record from the rails console, I got the error of the first image. I'm a new dev of RoR, someone can help me please?, Thanks!!
Without looking at the related models and their associations nothing is clear, because, it seems like your model associations are causing this error.
Model associations depict the relations between models (if its one-one, one-many and such) known as inheritance, very important concept in any object oriented programming. this is the way we implement it in rails
Go through this documentation.
It might help you get better understanding of rails associations.
Relatively new convert to Symfony2 from ZF1.
I have Googled and cannot seem to find the answer. Just wondering if there is a way to not render a view from a controller action in Symfony2.
In a ZF controller I could use:
$this->_helper->viewRenderer->setNoRender(true);
What is the equivalent in Symfony2?
In Symfony nothing is rendered for you automatically. If you need to render something, you have to do it explicitly. If you don't want to render, just don't do it :) Simply return a response:
return new Response();
Only job of a Symfony controller is to return a response. Rendering a template actually creates a response as well.
Wanted to give my Opinion:
Just because there is a possibility to render(ControllerMethod,{ params}) in a template doesn't mean you have to use it.
Doing so leads almost always to a shitty architecture, the turning point where projects start to be hard to debug, since you are mixing a VIEW (Presentation layer) with a CONTROLLER, that in turn renders another VIEW. You get the point.
Then when you have an error in the ControllerMethod, and instead you get a template error, not so nice isn't it ?
I vouch for strong architecture in software projects. This cheap solutions, like using this commodities, lead to the start of the bad. And I suggest to avoid it as much as you can unless there is no other possible way. And certainly there is!
That is the reason to use MVC. To separate Code from Presentation layer, start mixing both, and your architecture will leak.
I have found help for subclassing of a mapped superclass, and I have found help on how to map a TreeMap. However, I can not find anything that covers using a TreeMap in a subclass at all. Here is the situation: I am adding a function to a long-existing application. That application has mapped entities, a certain set of which, form a hierarchy. There is a , for instance that establishes the base class. Then there are many many MANY subclasses that use the elements to map the individual subclasses. The subclasses all use elements to reference the additional table that holds the attributes of the subclass. This has worked for several years and life has seemingly been good.
Now along comes my work effort and I need to use a TreeMap in my new subclass entity (extending the same base class as all of the others) so the first thing that I do is attempt to map it the same way other subclasses do, with a inside a .
Making the story short, I got an error when I started the app and Hibernate began mapping. Researching this error led me to review the DTD for hibernate mapping files and, guess what? According to my interpretation, one can not configure a Map of any kind inside a .
That same research exposed me to the which CAN contain a Map. So, off I go configuring a inside the base class mapping.
When I did this, I got bizarre errors referencing symbols that I can't even find in the code, in mappings.... anywhere! More research and I find a reference in the Hibernate reference manual, Chapter 9, that says that Hibernate does not support mixing of and elements. So that can't be done either.
My question is: is there a solution that I have missed along the way? From the sound of things it seems that you can NOT configure a map in a subclass if you are using because the inside it won't take a map.... and, while a Map can be configured in a , I doubt that I can gather up much support around here for wading through the current mapping files and re-mapping ALL entities as entities.
Has anybody got any ideas? If I am not looking at this right, believe me, I am willing to accept that and learn!
I have a custom implementation of a multi tenant code first system basically SQL Schema Divisions of the tenants. I am using the ToTable method to map the schema correctly on the first call, but as I have read about the model being cached changing the schema on the second call do a different tenant does not work. Is there any ways in EF 4.1 to disable the caching or to rebuild the model every time.. Yes i know this is not great for performance. Thanks for any help..
Although it is an old question, but for all those who face this issue and end up finding this question for a possible solution. Here it goes...
Initially caching could be turned off by setting the "CacheForContextType" property of the ModelBuilder to ‘false’ in the OnModelCreating method. This method is defined in DBContext as virtual and needs to be overridden. But in EF 4.1 this property has been removed, since model creation is an expensive process and the Microsoft team wanted to promote a better pattern. Check this link
It seems like the Build() command on the ModelBuilder is what you're looking for.
modelBuilder.Build().Compile().CreateObjectContext...
I have a database I'd like to create an entity from, and then generate RESTful output.
My objective is to add a property to one of the tables once it becomes an entity. The data for that property would be one I'd come up with through calculations done on a few different fields in the table. From there, the code generator would create RESTful output like it normally does.
I have managed to be able to update the SSDL, CSDL, and the mapping sections of the edmx file along with using the SampleEdmxCodeGenerator as a custom tool. When I have all the sections in the edmx file filled out with my custom property, the svc fails because (I'm assuming) the property doesn't exist in the database. If I leave the property out of the SSDL, but put it in the client schema (CSDL) and the mapping section, I can't build my project.
I've modified the partial class and added to it, but the problem there is that I need to populate the methods on the creation time of the class, and I haven't been able to do that yet.
Am I headed in the right direction, or is this not possible? It seems like I should be able to do this with minimal effort, but I keep hitting walls.
I think you're taking detours to get where you want. I haven't used either of these approaches (recently), so they might not do exactly what you're after, but you could try this:
Create a partial class file right next to the .edmx model, which has the same name as your entity.
In it, specify the property you want as a read-only property, that does the calculations on each get.
Partial Classes and Partial methods were the first part of my answer. What I'm essentially trying to do I can't do. I can manipulate data that is returned by using partial methods and partial classes. I can plug the OnmethodnameChanged() method to format the data how I'd like it to be shown, but that only gets me part way to my desired result.
What I would also like to do, is create a property c, which doesn't exist as a column in the database (and therefore does not exist in my entity), calculated from a couple different properties in the database (say a and b), and then add property c to the entity framework class. In doing this, I figured it would then get generated into the RESTful webservice output.
A problem that occurs comes from the need for the class to update any changes you make, and have it propagate back to the data source. I didn't care about that, because I want my property to be read only. From what I've gathered this isn't possible.
For reference, these two posts really helped:
Adding custom property to Entity Framework class
(I can only post one url currently, so here is the address to the other article)
social.msdn.microsoft.com/Forums/en-US/adodotnetdataservices/thread/b7a9e01d-c5c2-4478-8f01-00f7f6e0f75f
What I've decided to do, is to expose my entity as I've done so far, then consume the RESTful service that manipulates data and reformats it, and introduces needed properties. I'll turn the results into my own data object, and use that as a datasource to be exposed by yet another RESTful web service. I think this website gives a good example on how to expose a custom datasource.
mstecharchitect.blogspot.com/2008/12/surfacing-custom-data-source-in-adonet.html
If for some reason that is too slow, I suppose I could just make another table in my database that has a reworking of the data, and the calculated output in a format I'm looking for. The thing I want to avoid is having my resulting client having to do any of the data manipulation since it will be on some micro devices like palms, iphones, and blackberries.
Hope that helps anyone else with the same problem. It seems that is a shortfall in the current version of Data Services, but to some extent, I'm sure they'll be addressing it in later versions. Maybe T4 and .net 4.0 will be addressing it. I'm not sure.