獲取mongodb中所有字段的總和 c#

Question

我有一個 mongodb 看起來像這樣

[
{
    "client_id": "abc",
    "product_id": "123",
    "weight": {
        "value": 100
        "unit": "kg"
    }
},
{
    "client_id": "def",
    "product_id": "456",
    "weight": {
        "value": 200
        "unit": "kg"
    }
}
]

我需要使用 mongodb c# 客戶端獲取特定客戶端 ID 和產品 ID 的權重值總和，我該怎么做？

我試過了，但它總是返回 0

var total_weight = await Collection.AsQueryable()
                        .Where(
                        x => x.client_id == "abc" &&
                        x => x.product_id== "123")
                        .SumAsync(x => x.weight.value);

謝謝

Answer 1

我想你正在尋找這個查詢，所以你可以試試這個代碼：

var total_weight = await Collection.AsQueryable<YourModel>()
                .Where(x => x.client_id == "abc" && x.product_id == "123")
                .GroupBy(x => new { x.client_id, x.product_id })
                .Select(x => x.Sum(y => y.weight.value))
                .FirstOrDefaultAsync();