Get last price by user role? - sql

Question

How do I get the last price claimed by the retailer b#gmail.com (the 5th row in the price table) with the condition that the role = 'retailer' ?
So here is my simple table:
table users (using Entrust Role package with the default relationship in the model)
__________________________
| id | email | password |
|-------------------------|
| 1 | a#g.com | 123 |
| 2 | b#g.com | 123 |
| 3 c#g.com | 123 |
| 4 d#g.com | 123 |
--------------------------
table roles (using Entrust Role package with the default relationship in the model)
______________
|id | name |
|--------------|
|1 | customer |
|2 | retailer |
----------------
table role_user (using Entrust Role package with the default relationship in the model)
__________________
|id_user | id_role|
|------------------|
| 1 | 1 | -> a#gmail.com is a customer
| 2 | 2 | -> b#gmail.com is a retailer
| 3 | 1 | -> c#gmail.com is a customer
| 4 | 1 | -> d#gmail.com is a customer
------------------
Here is the tricky part how to query the price:
I have the following prices table (Users can post 1 or more prices. Look at the relationship below):
____________________
|id| user_id| price |
|--------------------|
|1 | 1 | 10.00 | -> price claimed by a customer a#gmail.com
|2 | 2 | 5.00 | -> price claimed by a retailer b#gmail.com
|3 | 1 | 6.00 | -> price claimed by a previous customer a#gmail.com
|4 | 3 | 5.00 | -> price claimed by a customer c#gmail.com
|5 | 2 | 7.00 | -> price claimed by a previous retailer b#gmail.com //How to get this one? This is the last price claimed by the retailer.
|6 | 3 | 8.00 | -> price claim by a customer c#gmail.com
---------------------
The relationship in my Price model:
class Price extends Model{
public function product()
{
return $this->belongsTo('App\Product');
}
public function user()
{
return $this->belongsTo('App\User');
}
How do I get the last price claimed by the retailer b#gmail.com (the 5th row in the price table) with the condition that the role = 'retailer' ?
The purpose is to get the last price that the retailer has claimed.
Update my question:
I want to access the price claimed by the last retailer from my Product model using the $products variable.
A sample table product that I have:
_______________________________
|id | user_id| name |
|------------------------------
| 1 | 1 | Milk |
| 2 | 2 | Phone |
| 3 | 1 | computer |
| 4 | 1 | Banana |
------------------------------
My Product.php model relationship:
class Product extends Model{
public function prices()
{
return $this->hasMany('App\Price');
}
}
So, in my ProductController.php I send the $product variable to the view like this:
class ProductController extends Controller
{
public function show($id)
{
$product = Product::where('id', '=', $id)->
return view('products.show')->with('product', $product);
}
}
and in my view show.blade.php, I loop through the $product variables and I can display the prices claimed for the product.
#foreach($product->prices as $price)
<li>Price claimed: {{$price->price. " " }} </li>
#endforeach
I want to get like something like
$price_last = $product->prices()->where(role, 'retailer')->last().
dd($price_last);
The last() function there is the last price that the retailer claimed but this code is just example. How do I achieve this?
Please let me know if you need more information.

Answer 1

You're looking for the whereHas method:
$query = Price::latest('id')->whereHas('user', function ($query) {
$query->whereHas('role', function ($query) {
$query->where('name', 'retailer');
});
});
$price = $query->value('price');
This assumes you've set up the relationships between your User, Role and Price models.