Difference Between One-to-Many, Many-to-One and Many-to-Many?
Ok so this is probably a trivial question but I’m having trouble visualizing and understanding the differences and when to use each. I’m … Read more
many-to-many
Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by: Model.find_or_create_by_<attribute>(:<attribute> => “”) But what if I need to find_or_create by more than … Read more
How do I make many-to-many field optional in Django?
When you have a many-to-many relationship (related_name, not through) and you are trying to use the admin interface you are required to enter … Read more
Create code first, many to many, with additional fields in association table
I have this scenario: public class Member { public int MemberID { get; set; } public string FirstName { get; set; } public … Read more
What is related_name used for?
What is the related_name argument useful for on ManyToManyField and ForeignKey fields? For example, given the following code, what is the effect of … Read more