I am a bit confused with Laravel and relationships in general.
I have 2 tables:
coffees with fields: id, name, blend (int(1))
blends with fields: id, blend_id (Will be id from coffees table), coffee_id (Will be id from coffees table), percent
If the blend field value is 1, it is a blend and it should have a few records on the blends table.
So I have 2 questions:
Which relationships do I have here (belongsTo, hasMany, not sure)
How do I get all the coffees for a blend ordered by their names.
In my models I have:
Coffee:
public function blend()
{
return $this->hasMany('App\Blend', 'blend_id');
}
Blend:
public function coffee()
{
return $this->belongsTo('App\Coffee');
}
Got a bit lost here, thx
Related
I would like to do the following:
Product can have one Supplier. The Supplier contains some data like a name. Additionally there is a pivot-value that should be stored for Supplier that is assigned to Product (e.g. a delivery_service-string).
Example:
Product: A yummy Banana
Supplier: Banana Inc
-> If the Product "A yummy Banana" is supplied by Supplier it should be delivered by DHL. The important thing: You can not add DHL as a field to Supplier, as each Product to Supplier-relation should have it's own delivery-service-field.
As there can be many Products but each Product can only have one Supplier I thought about something like this:
Product
Schema:
- id
- supplier_id
Relation
public function supplier()
{
return $this->belongsTo(Supplier::class);
}
Supplier
Schema:
- id
- name
Relation
public function products()
{
return $this->hasMany(Product::class);
}
This works, but unfortunately I can not store pivot data in the supplier() relation.
At the moment I could imagine to store the value not in a pivot table but in a new row in the Product's schema. But I don't think this is the best way.
Any suggestions? :-)
One item have many childs
This is one-to-many
You need to store item_id in your child table
Item Table
id, name
Child Table
id, item_id, type
If you have a case EG
Each child can have a favorite item then you will have to create a many-to-many relation between them. (Which will be a separate relation)
Create a table "child_item" (pivot)
Child Item Table
child_id, item_id
then create a relation in your laravel
class User extends Model{
...
public function favorites(){
return $this->belongsToMany(Items::class); // Include the path using "use" on top
}
}
So now you get your 2 relations between child and item
One item can have many children
Many children can mark items as favorites
I'm learning Laravel and Laravel eloquent at the moment and now I try to solve a problem using relations in Laravel.
This is what I want to archive:
The database holds many sport clubs. A sport club has a lot of teams. Each team has games. The teams table has a column named club_id. Now I want to create Eloquent relations to get all games of a club.
Here is what I got so far:
Club model
id => PRIMARY
public function games()
{
return $this->hasMany('App\Models\Games')->whereHas('homeTeam')->orWhereHas('guestTeam');
}
Game model
home_id => FOREIGN KEY of team ; guest_id => FOREIGN KEY of team
public function homeTeam()
{
return $this->belongsTo('App\Models\Team','home_id')->where('club_id','=', $club_id);
}
public function guestTeam()
{
return $this->belongsTo('App\Models\Team','guest_id')->where('club_id','=', $club_id);
}
Team model
id => PRIMARY ; club_id => FOREIGN
In my controller all I want to do is Club::findOrFail($id)->games()
Executing the code above returns a SQL error that the games table does not have a column named club_id.
What is the correct way to create this kind of relation?
Thanks!
EDIT
Thanks to Nikola Gavric I've found a way to get all Games - but only where club teams are the home or away team.
Here is the relation:
public function games()
{
return $this->hasManyThrough('App\Models\Game','App\Models\Team','club_id','home_id');
}
How is it possible to get the games where the home_id OR the guest_id matches a team of the club? The last parameter in this function does not allow an array.
There is method to retrieve a "distant relationship with an intermediary" and it is called Has Many Through.
There is also a concrete example on how to use it which includes Post, Country and User, but I think it will be sufficient to give you a hint on how to create games relationship inside of a Club model. Here is a link, but when you open it, search for hasManyThrough keyword and you will see an example.
P.S: With right keys naming you could achieve it with:
public function games()
{
return $this->hasManyThrough('App\Models\Games', 'App\Models\Teams');
}
EDIT #01
Since you have 2 types of teams, you can create 2 different relationships where each relationship will get you one of the type you need. Like this:
public function gamesAsHome()
{
return $this
->hasManyThrough('App\Models\Games', 'App\Models\Teams', 'club_id', 'home_id');
}
public function gamesAsGuests()
{
return $this
->hasManyThrough('App\Models\Games', 'App\Models\Teams', 'club_id', 'guest_id');
}
EDIT #02
Merging Relationships: To merge these 2 relationships, you can use merge() method on the Collection instance, what it will do is, it will append all the records from second collection into the first one.
$gamesHome = $model->gamesAsHome;
$gamesGuests = $model->gamesAsGuests;
$games = $gamesHome->merge($gamesGuests);
return $games->unique()->all();
Thanks to #HCK for pointing out that you might have duplicates after the merge and that unique() is required to get the unique games after the merge.
EDIT #03
sortBy also offers a callable instead of a attribute name in cases where Collection contains numerical indexing. You can sort your Collection like this:
$merged->sortBy(function($game, $key) {
return $game->created_at;
});
When you define that Club hasMany games you are indicating that game has a foreign key called club_id pointing to Club. belongsTo is the same but in the other way. These need to be coherent with what you have on your database, that means that you need to have defined those keys as foreign keys on your tables.
Try this...
Club model
public function games()
{
return $this->hasMany('App\Models\Games');
}
Game model
public function homeTeam()
{
return $this->belongsTo('App\Models\Team','home_id');
}
public function guestTeam()
{
return $this->belongsTo('App\Models\Team','guest_id');
}
Your Query like
Club::where('id',$id)->has('games.guestTeam')->get();
I am working on a team sports statistics project in Laravel.
Here is a sketch of the main models regarding this question:
class Team
// belongsToMany matches
// belongsToMany people
class Match
// belongsToMany teams
// belongsToMany people
class Person
// belongsToMany matches
// belongsToMany teams
I have also made models for the pivot tables to work directly with them. I have some stuff like goals_scored, number, position etc. stored there and it's too clumsy to use methods for updating pivot.
class MatchTeam // Participation of a team in the match
// belongsTo match
// belongsTo team
class MatchPerson // Participation of a person in the match
// belongsTo match
// belongsTo team
// belongsTo person
Is there an Eloquent way to relate MatchTeam to MatchPerson? I don't want to introduce a direct match_team_id foreign key, I want to do this using the existing match_id and team_id fields on both of the tables.
Currently I have this in my MatchTeam model:
public function matchPeople() // the roster
{
return $this->hasMany('App\Stats\MatchPerson', 'team_id', 'team_id')->where('match_id', $this->match_id);
}
It works fine. However, I am very concerned that this code is not fair to the nature of the relation - they are not related based on team_id, they are related based on both fields. I could have also written it like this:
public function matchPeople() // the roster
{
return $this->hasMany('App\Stats\MatchPerson', 'match_id', 'match_id')->where('team_id', $this->team_id);
}
Is there a fair way in which I could specify relation based on two columns in Eloquent?
Of course, this question is more out of curiosity as the actual problem of making the method is conquered.
A usage example for the curious:
$teamA->goals_for = $teamA->matchPeople->sum('goals');
I have a quick question on how to define the below relationship
I have a USER that can belong to Many Councils, Many Schools and Many Businesses.
Now I know I can have a pivot table for all the above something like
council_user
school_user
business_user
This means I can pull out of the DB all councils a user belongs to, all businesses etc
To save me doing this is there a better approach that having 3 pivot tables, could I use Many To Many Polymorphic Relations and do it that way, if so does any one know how that would look as a table structure?
I feel it would be something like...
business
id - integer
name - string
council
id - integer
name - string
school
id - integer
name - string
userables
user_id - integer
userable_id - integer
userable_type - string
If so do I remove the userable_is and userable_type from my USER table and have this extra userables table?
Does any one know how this works, have I totally misunderstood what Polymorphic Relations does?
In Many to Many polymorphic relationship, you should have userables table along with users table. and userable_id and userable_type should be in userables table not in users table.
userables table:
user_id userable_id userable_type
1 1 App\Business
1 2 App\School
...
Business, School and Council Model:
public function users()
{
return $this->morphToMany('App\User', 'userable');
}
User Model:
public function businesses()
{
return $this->morphedByMany('App\User', 'userable');
}
public function schools()
{
return $this->morphedByMany('App\User', 'userable');
}
public function councils()
{
return $this->morphedByMany('App\User', 'userable');
}
then, this gives all the businesses of user with user_id 1.
$users=User::find(1);
foreach($user->businesses as $business)
{
print_r($business->name);
}
See Many to many polymorphic relation in doc.
I've got a situation in a project where I need to form a relationship between a primary key on one table and an indexed column (not the primary key) on another. Here's a sample of the database layout:
courses table
id
level
resources table
id
courses_resources table
course_level
resource_id
In my CourseResource model I have the following:
public function courses(){
return $this->belongsToMany('Course', 'courses_resources', 'resource_id', 'course_level');
}
Which works fine.
Then in my Course model I have:
public function resources(){
return $this->belongsToMany('CourseResource', 'course_resources', 'course_level', 'resource_id');
}
Which doesn't work. When I look at the last query performed on the database, it appears Laravel is searching the course_level column using the course's ID. That makes sense, but is there any way to use the level column for this relationship?
Eloquent BelongsToMany depends on PKs, so there is no way to do that with its methods.
You need custom relation object for this, that will check for given field, instead of primary key.
A quick and hacky solution would be this:
// Course model
public function getKey()
{
$relation = array_get(debug_backtrace(1, 2), '1.object', null);
if (method_exists($relation, 'getForeignKey')
&& $relation->getForeignKey() == 'courses_resources.course_level')
{
return $this->getAttribute('level');
}
return parent::getKey();
}
However if you would like to use it in production, do some extensive testing first.