I have a few Entities that I would like to be able to map Comments to (Profiles, Posts, Images, Videos - things like that).
Each of these Entities has a column that contains a guid, and what I would like to do is have the Comment table hold the guid to the item to which it belongs. What I can't figure out is how to configure Doctrine to handle this kind of thing so that the joins work. The solution I think might work is to use NativeSql (although I am not sure that will work either), but would rather not have to do that if at all possible.
I don't imagine I am the first one to encounter this problem, so I hope someone out there can help!
Thanks.
I think you can use inheritance mapping for that, can't you? You will need something like CommentableEntity, from which Profiles, Posts, Images, Videos are inherited.
It adds some overhead and you need to check if it's ok for your task.
Related
I am designing a master/detail solution for my app. I have searched for ever in the django docs, also here and elsewhere I could, so I guess the answer is not that obvious, despite being an answer many people look for - not only in django, but in every language, I think.
Generally, in most cases, the master already exists: for example, the Django Docs illustrate the Book example, where we already have an Author and we want to add several Books for that Author.
In my case, the parent is not yet present on the database think of a purchase order, for instance.
I have thought to divide the process in two steps: the user would start to fill in the info for the master model (regular form) and then proceed to another view to add the lines (inline formset). But I don't think this is the best process at all - there are a lot of possible flaws in it.
I also thought about creating a temporary parent object in a different table and only having a definitive master when the children are finally created. But it still doesn't look clean.
Because of that, for my app it would be ideal to create the master object at the same time as the detail objects (lines) - again, like an order.
Is there a way where I can have the same view to manage both master and detail? Like this I would receive both in the same POST request and it would make a lot more sense, not to say it would be much cleaner.
Sorry if it's too long, and thank you in advance!
So I found out that in my case the process could actually be split in two phases.
For this I simply use the traditional model form and inline formset.
But! I also found out that there could be several answers to this:
We could get crazy and build some spaceship in AJAX that would get the job done, simply by sending a JSON object (in which the lines could be an array of objects)
Django also has its ways and it's possible to send multiple forms in the same request! (thank you #mousetail for the tip).
Of course, be there as it may, there are many ways to build a house, these are just the ones I found out.
I'd like to augment events/occurrences in django-scheduler with three things:
Location
Invitees
RSVPs
For Location, my initial thought was to subclass Event and add Location as a foreign key to a Location class, but my assumption is that each occurrence saved won't then include Location, so if the location changes for one occurrence, I'll have nowhere to store that information.
In this situation, is it recommended to create an EventRelation instead? Will I then be able to specify a different Location for one occurrence in a series? The EventRelation solution seems untidy to me, I'd prefer to keep models in classes for clarity and simplicity.
I think Invitees is the same problem, so presumably I should use a similar solution?
For RSVPs, I intend to make an RSVP class with Occurrence as a foreign key, and as far as I can tell that should work without any issues as long as I save the occurrence before attaching it to an RSVP?
I've read all the docs, all the GitHub issues, various StackOverflow threads, the tests, the model source, etc, but it's still unclear what the "right" way to do it is.
I found a PR which introduces abstract models: https://github.com/llazzaro/django-scheduler/pull/389 which looks like exactly what I want, but I'm reluctant to use code which was seemingly abandoned 18 months ago as I won't get the benefit of future improvements.
EDIT: I'm now thinking that another way to do this would be to have just one object linked to the event using EventRelation, so I'd have an "EventDetails" object connected to the Event via EventRelation, then include FKs to Location, Guests, etc from that object.
I should then also be able to subclass my EventDetails object with different kinds of events and attach those too. I'll give it a go ant see if it works!
Just in case anyone find this and is wondering the same thing: I ended up ditching Django-scheduler and using Django-recurrence instead. Had to do a bit more work myself, but it was easier to create the custom event types that I was looking for. Worked pretty well!
I had problem with saving relation to object with same class as parent.
You can check this problem here.
When I read that I can easily set the relationship after the promise has fulfilled here I created another example with that info in mind. But it doesn't work as I expect.
What I expect
Create array of Box instances with relation to previous Box instance in each.
And the question is if I'm doing something wrong or it's a bug. Let me know if you need any informations.
Your example isn't clear and simple enough. It needs to be isolated to EXACTLY what you're having an issue about and nothing else.
Having said that, I have had quite a bit of success saving relations to objects with the same class as parent, and so I don't think this is a problem with Ember Data or Ember.
Your code is quite convoluted and uses the sync library, which I'm not faimilar with.
It's a good idea to things as simply as possible at first, so try creating a jsbin with just the isolated functionality relating to saving relations that you're attempting, and then adding additional layers of functionality and testing after each add.
I'd like to list all active products (from all or a specific category) in a template. I've looked almost everywhere and I simply cannot find a way to do this.
I want to display them in the footer of the shop (10 products from 1 category). That means show them without selecting product category.
Is this even possible? Products are only listed in the category template...
I'm using Satchmo 0.9.2
EDIT: Somehow I've missed this:
http://www.satchmoproject.com/docs/dev/customization.html
So it's solved...
Thank you!
this is a more general answer since there isnt any answer yet, so dont beat me. You also have to know that I never used satchmo, I never had a look at it.
But despite this, if I had to deal with your situation, I would have a look at the source code.
You might find answers there to develop something custom for your situation. This can be a tricky task but at least its worth a try.
There have to be models which store the data for your product and categories. Have a look at them and the views that retrieve the products from the database to render them. Also a look into the database cant hurt (think of phpmyAdmin to have a nice webbased interface).
It can be helpful to fire up your ./manage.py shell, import your/satchmos product and category models and play around with them.
A possible solution then could be to write a custom context_processor which retrieves the needed products/categories and passes these products from a category to your footer on a more global basis. Have a look here https://docs.djangoproject.com/en/1.3/ref/templates/api/#writing-your-own-context-processors. Maybe a custom middleware could also be a possibility. https://docs.djangoproject.com/en/dev/topics/http/middleware/#writing-your-own-middleware
I hope this helps. At least worth a try :)
I have a project with an FAQ app. The app has models for FAQ (written by the site authors) and UserFAQ (written by users-- not just a clever name). I want to return all entries, FAQ or UserFAQ that match certain conditions, but I also want to exclude any UserFAQs that don't match a certain criteria. Ideally, it would looks something like:
faqs = FAQ.objects.filter(question__icontains=search).exclude(show_on_site=False)
Where "show_on_site" is a property that only UserFAQ objects have. That doesn't work because the filter craps out on the parent class as it doesn't posses the property. What's the best way of doing this? I came across this snippet, but it seems like overkill for what I want to do.
In your position, absent a need to have two tables, I'd be tempted to have one FAQ model/table with is_user_faq and show_on_site fields.
Sometimes it helps when modeling data to organize it for simple and fast access. While model inheritance has some appeal, I've found it it's often easier to avoid using it.