Model Association Question

Profile model association question

This is really a design decision that needs to be decided by how its going to be used.

I've recently created a program that has a 'user' and 'profile' model separated with the 'user' always having the a 'profile' constraint.

I did it this way since there is nothing in the 'user' table other then information needed to login a user or allow the admin to see/do certain things.

Whereas the 'profile' model contains data that can be viewed and searched on by other members.

But again, its a design decision you have to make based on how the data will be used.

Rails 6 & Model Association and/or Migrations

add_reference is meant to be a shortcut as part of the rails convention, under the hood, it will call add_column and other options that you specify [you can check the code for rails-6 here]

while foreign keys are not required, they are considered a best practice because they guarantee referential integrity. you can read more about it here https://edgeguides.rubyonrails.org/active_record_migrations.html#foreign-keys

or is it the same? Doesn't the second option create indexes as well whereas the first does not?

having said that, your 2 migrations are not entirely the same even though they work the same (they achieve the same goal) - the second option will add an index by default unless you specify the option not to - I definitely agree with you about using add_reference as this is an easier and more foolproof shortcut

of course, you can also achieve that manually by using your first migration by adding an index and a foreign key as well

add_column :users, :course_id, :integer
add_index :users, :course_id # uniq or not
add_foreign_key :courses, :users

CakePHP Model Association question

No, technically you only need to specify the associations between models in the directions you are going to use. If you are never going to use an association in a certain direction, then you do not need to specify it.

Rails: Model.association vs Model.association.all

CollectionProxy vs AssociationRelation

Here is an explanation from a previous SO question that might help you out.

Trouble with model associations

Generally you are right.

We want users to follow a shop, and a shop can create rewards and grant many rewards to many followers.

1. Visual schema:

2. Model associations (complete version)

user.rb

has_many :follows
has_many :reward_follows, through: :follows
has_many :rewards, through: :reward_follows # NOT through shops
has_many :shops, through: :follows

follow.rb

belongs_to :user
belongs_to :shop
has_many :reward_follows

shop.rb

has_many :rewards
has_many :reward_follows, through: :rewards # NOT through follows
has_many :follows
has_many :users, through: :follows

reward.rb

has_many :reward_follows
belongs_to :shop
has_many :follows, through: :reward_follows
has_many :users, through: :follows

3. Do not use date field. Use datetime field.

Justification: https://www.ruby-forum.com/t/time-without-date/194146

This personally saved me hours of work long-term.

Laravel model association advice

Probably in your store model:

public function managerRelation() 
{
    return $this->hasOne('user', 'user_id', 'manager');
}

For those columns

users->user_id
stores->manager

On your User model

public function managerOf() 
{
    return $this->belongsToMany('store', 'stores', 'manager', 'id');
}

You should consider adding _id to all your id columns, like, manager_id.

EDIT:

Another problem is that manager is already a column in your table, so your relation cannot be manager(), or you'll have to the column to manager_id. I temporarily renamed it to managerRelation so you should be able to:

echo $store->managerRelation->user_id;

Ruby on Rails model associations nubie question

Your areas table needs a book_id integer field to match against the books table's primary key.

Could not find the association :catorizations in model

Could not find the association :catorizations in model Question

You have a typo in Question model

This

has_many :categories, through: :catorizations

should be

has_many :categories, through: :categorizations

---

Related Topics