Laravel Relationships

relationship

one to one

• hasOne('Model\Name','foreign_key','local_key')
• belongsTo('Model\Name','foreign_key','local_key')

one to many

• hasMany('Model\Name','foreign_key','local_key')
• belongsTo('Model\Name','foreign_key','local_key')

many to many

• belongsToMany('App\Role', 'role_user', 'user_id', 'role_id')
• role_user table

~

• role->attach($id|array $ids)
• role->detach($id|array $ids) / role->detach()
• role->sync([])
• role->toggle([])

hasOneThrough

• hasOneThrough('Model\Name','Model\Name1','foreign_key1','foreign_key','local_key','local_key1')

hasManyThrough

• hasManyThrough('Model\Name','Model\Name1','foreign_key1','foreign_key','local_key','local_key1')

Polymorphic

• $this->morphTo(); -> App\Image
• $this->morphOne('App\Image', 'imageable')

~

• imageable_type -> model/name
• imageable_id -> id

Eager Loading

$user = User::with(['message'])->get();
# retrive specific column
$user = User::with(['message:title,time'])->get();
# nested
# reply function inside message model
$user = User::with(['message.reply'])->get();

• access

foreach ($users as $user) {
    echo $user->message->title;
}

resource

• pivot