How to count items where foreign key is repeated? - php

Question

How I can count items with same foreign key and still get acces to relationship data?
I'm using PHP - Laravel - Eloquent, and have three tables: User, User_items and items.
User_items has three columns: id, user_id and item_id:
ID | user_id | item_id
0 | 5 | 2
1 | 5 | 3
2 | 5 | 8
3 | 5 | 3
Let's say items also has three columns: id, name and value:
ID | Name | Value
2 | Sword | 500
3 | Pickaxe | 250
8 | Shovel | 700
I want to count items with the same user_id and return item data from the items table. In order to get all of the user items, I'm using the following relationship:
public function user_items()
{
return $this->hasMany(User_items::class, 'user_id', 'id');
}
Next, I want to get the names of these items and count them. I don't just want:
Sword
Pickaxe
Shovel
Pickaxe
I want, somehow, to get the results like this:
2 Pickaxe
1 Sword
1 Shovel
My user_items relationship, to get the data about an item looks like :
public function item_data()
{
return $this->hasOne(Items::class, 'id', 'item_id');
}
Thats how I'm getting repeatable result:
return response()->json(["DATA" => $user->user_items->load('item_data')->toArray()], 201);
Example output
"DATA":[
{
"id":1,
"item_id":5,
"created_at":"2019-06-04 08:44:08",
"updated_at":"2019-06-04 08:44:08",
"item_data":{
"id":5,
"name":"Sword",
"rarity":"good",
"value":500,
"image":"image.jpg",
"color":"#3160ed",
"created_at":null,
"updated_at":null
}
},
}
I want to add a row like "count": 5 to the above output.

Answer 1

I reckon what you need is a many-to-many relationship between a user and an item.
I rename the tables like this for better naming convention: users, user_item, items.
class User
{
public function items()
{
return $this->belongsToMany(Item::class)
}
}
For each user to return the items and the number of items for each. You might do something like.
$items = $user->items()->select('items.*', 'count(items.id) AS items_count')
->groupBy('items.id')
->get()
->toArray();
// From the controller, this array will be automatically converted to json.
return ['DATA' => $items];
You will have something like this. Not exactly the format you want, but I think it's better keep it this way.
[
'DATA' => [
{
"id":5,
"name":"Sword",
"rarity":"good",
"value":500,
"image":"image.jpg",
"color":"#3160ed",
"created_at":null,
"updated_at":null,
items_count: 1
}
]
]