对于雄辩的关系联接几乎没有什么困惑,因为到目前为止,我以前都是通过查询生成器来获得结果的。仍然提到其他相关问题,我不清楚。请用一个更好的例子向我解释。
现在,我要列出与客户相关的商品详细信息。
将customer_items与其中customer.id = customer_items.user_id和items.id = customer_items.item_id的项目一起加入。
答案 0 :(得分:1)
首先,您需要这样定义模型:
class Customer extends Model
{
protected $table = 'customers';
public function items(){
return $this->hasMany(Item::class, 'customer_id');
}
}
class CustomerItem extends Model
{
protected $table = 'customer_items';
public function customer(){
return $this->belongsTo(Customer::class, 'customer_id');
}
}
然后您将这种关系称为:
$customer = Customer::find(1); // This will get the first customer in the DB
$itemsOfCostumer = $customer->items // This will return all the items of the customer
// Now let suppose we have an ItemCustomer and we would like to know the owner
$customerItem = CustomerItem::find(1); // Get the first item of a customer in DB
$customer = $customerItem->customer; // Ther you have the customer
这只是一个小例子。 Stackoverflow不是一个教育性网站,我强烈建议您访问Laravel Relationship Docs。在那您可以学到更多,他们在Laracast上有一个非常好的关于关系的系列文章(如果您是视觉学习者)https://laracasts.com/series/eloquent-relationships
答案 1 :(得分:1)
首先在模型中定义方法。
Customer.php // Customer model
class Customer extends Model
{
protected $table = 'customers';
protected $primaryKey = 'customer_id';
public function customerItems(){
//customer_id is a foreign key in customer_items table
return $this->hasMany(Item::class, 'customer_id');
// A customer will has many items thats why hasMany relation is used here
}
}
CustomerItem.php // CustomerItem
class CustomerItem extends Model
{
protected $table = 'customer_items';
protected $primaryKey = 'customer_item_id';
public function itemDetail(){
//customer_id is a foreign key in customer_items table
return $this->hasOne(Customer::class, 'customer_item_id');
//A Item will has single detail thats why hasOne relation used here
}
}
在CustomerController.php
use \Customer // define customer model path
public function getCustomerItem(Request $request)
{
// Eloquent query to get data
$customer_item_detail_data = Customer::with('customerItems.itemDetail')->get();
//it return all items of customers with item details
//$customer_item_detail_data = Customer::with('customerItems')->with('customerItems.itemDetail')->get(); you can also use in this way
}
希望有帮助。谢谢。
答案 2 :(得分:0)
如果我很好地回答了您的问题,那么您正在寻找查询以获取商品详细信息。
$item_details = Items::
join('customer_items', 'customer_items.item_id', '=', 'items.id')
->join('customer', 'customer.id' '=', 'customer_items.customer_id');
或者您可以通过执行以下操作获得相同的结果
$item_details = DB::table('items')
->join('customer_items', 'customer_items.item_id', '=', 'items.id')
->join('customer', 'customer.id' '=', 'customer_items.customer_id');