我想用laravel,写这个查询
我的表格结构是
有一个用户id$user_id=身份验证::id((;
购物车->ID|USER_ID|FOOD_ID|数量|状态
食物->ID |名称|价格
SELECT sum(food.price*carts.quantity) as total
from carts
left join food on carts.food_id=food.id
where user_id=$user_id and status='0'
您也可以尝试这种方式:
$res = DB::table('carts')
->select(DB::Raw('SUM(food.price*carts.quantity) AS total'))
->leftJoin('food', 'carts.food_id', 'foods.id')
->where('carts.user_id', $user_id)
->where('carts.status', 0)
->first();
使用查询生成器:
$amount = DB::table('carts')
->where('carts.user_id', $user)
->where('carts.status', '!=', 0)
->leftJoin('foods', 'carts.food_id', 'foods.id')
->sum(DB::raw('carts.quantity * foods.price'));