渴望从laravel 5.4中相关表的多个值中加载第一项

Question

I have two tables 'purchases' and 'accounts_purchase_history'. purchase has many accounts history. So I need to get all the purchases with the latest history. What i have done so far

 $purchases = Purchases::with(['accounts_purchase_historie' => function($query){
            return $query->orderBy('id','DESC')->first();
        }])->orderBy('id','DESC')->where('status','extended')->get();

But this query only gets the first purchase history, How can i solve this?

Answer 1

You can use a HasOne relationship:

public function latest_history() {
    return $this->hasOne(...)->orderBy('id','DESC');
}

$purchases = Purchases::with('latest_history')
    ->orderBy('id','DESC')
    ->where('status','extended')
    ->get();

foreach($purchases as $purchase) {
    $purchase->latest_history
}

However, this will still fetch all the histories from the database in the background.