Although the documentation of the add method does not mention it, you can actually pass directly an id to it, like this: my_instance.add(id) Surely, this only works when the primary key is used as the identifier for the relation (the default behaviour).
Keep in mind that the name you give to your strong parameters (employees, employee_ids, etc.) is largely irrelevant because it depends on the name you choose to submit. Strong parameters work no “magic” based upon naming conventions. The reason https://gist.github.com/leemcalilly/a71981da605187d46d96 is throwing an “Unpermitted parameter” error on ’employee_ids’ is because it is expecting an array … Read more
It’s a straightforward inner join of the tables: SELECT m.name, cp.id_category FROM manufacturer as m INNER JOIN product as p ON m.id_manufacturer = p.id_manufacturer INNER JOIN category_product as cp ON p.id_product = cp.id_product WHERE cp.id_category = ‘some value’
Edit: I’ve written this up in 3 blog posts with code part 1 sets up the solution and creates a new user part 2 adds the courses and saves them with the user profile part 3 allows editing and deletion of users and their courses Github source: https://github.com/cbruen1/mvc4-many-to-many I think you’ve strayed from conventions a … Read more
The terms Left and Right in MapLeftKey and MapRightKey in the many-to-many mapping with Fluent API can be misunderstood and I guess your problem is caused by this misunderstanding. One might think that it means they describe the columns that are “left” and “right” in the many-to-many join table. That’s actually the case if you … Read more
What you had likely done is that you created new instance of Article and and some new instance(s) of HeaderField. These instance(s) of HeaderField were then associated with Article. After that trying to persist Article fails, because as error message says, it refers to new objects and relationship is not marked as PERSIST. Additionally according … Read more
I agree with everything Oded said except “It can’t reasonably be used as a foreign key either.” In this case it’s a pick your poison, the mapping table absolutely can be a parent, it’s just a matter of the child using a multicolumn FK or not. Take a simple case of Car and color. Each … Read more
Ok, this is my solution using above classes. I added a bunch more filters to filter it correctly, but I wanted to make the code readable here. This is exactly what I was looking for, and I found my solution here: http://www.slideshare.net/lincolnloop/customizing-the-django-admin#stats-bottom (slide 50) Add the following to my admin.py: class CustomerForm(forms.ModelForm): def __init__(self, *args, … Read more
OK, after a lot of research, I realized that it was my own ignorance of SQL terminology that was holding me back. My search for a solution to find users belonging to “at least one of” the list of groups should have been to find users belonging to “any” of the list of groups. The … Read more