Laravel querying multiple related models - php

Question

For example: I have these models in my application.
User, Profile, Interest.
I linked the users table with the profiles table by adding the user_id column in the profiles table. And I linked profiles and interests by using a pivot table (interest_profile), Which is (as obvious) will have two columns (profile_id, interest_id).
However, I want to query the users who are associated with a profile, too see who is associated with a particular interest, In other words: "select all users who are having (in their profiles) that particular interest".
I know that I can do this with raw SQL by joining the four tables and then use (where clause).. But I want to do it the Laravel way.
Thanks in advance.

Answer 1

First make sure you have your relationships setup correctly on your models like:
class User extends Model
{
public function profile()
{
return $this->hasOne(Profile::class);
}
}
class Profile extends Model
{
public function user()
{
return $this->belongsTo(User::class);
}
public function interests()
{
return $this->belongsToMany(Interest::class, 'interest_profile');
}
}
class Interest extends Model
{
public function profiles()
{
return $this->belongsToMany(Profile::class, 'interest_profile');
}
}
Then you can use whereHas() to constrain a query by a related model and dot notation for nested relations. So your query would be:
User::whereHas('profile.interests', function($query) use ($interestName) {
return $query->where('name', $interestName);
})->get();
That would just return a collection of users. If you wanted to return their profiles and interests as well you would use with():
User::whereHas('profile.interests', function($query) use ($interestName) {
return $query->where('name', $interestName);
})
->with('profile.interests')
->get();

Answer 2

Assuming the User model has a relationship profile and the Profile model has a relationship interests, you can do this.
$interest_id = 1;
$users = User::whereHas('profile', function ($query) use ($interest_id) {
$query->whereHas('interests', function ($query) use ($interest_id) {
$query->where('id', $interest_id);
});
})->get();