获取mongodb中所有字段的总和 c#

Question

我有一个 mongodb 看起来像这样

[
{
    "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# 客户端获取特定客户端 ID 和产品 ID 的权重值总和，我该怎么做？

我试过了，但它总是返回 0

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

谢谢

Answer 1

我想你正在寻找这个查询，所以你可以试试这个代码：

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();