Linq to Sql Sum，无记录 [英] Linq to Sql Sum with no records

问题描述

我正在创建一种方法，该方法收集一个月中的累计总数.问题在于，在给定的月份中某些项目可能不收费，因此不会返回任何行.

I am creating a method that collects accumulated totals throughout the month. The problem is that there may not be charges for some of the items in a given month so no rows would be returned.

我可以看到在没有数据的情况下如何出错:

I can see how this would error with no data:

double fuelCost = (double)(from a in db.EquipmentFuelLogs
                           where a.wdEquipmentMainGeneralOID == vehicleKey &&    
                                (monthBeginDate < a.Date1 && a.Date1 < monthEndDate)
                           select a.TotalCost).Sum();

检测该月没有任何燃料交易并将燃料成本设置为0的最佳方法是什么?只是尝试一下? 本文谈到了这个问题，但没有办法.

What is the best approach to detect no fuel transactions for that month and set the fuel cost to 0? Just do a try catch? This article spoke of the problem but no solution.

推荐答案

我添加了一个catch来捕获错误.我从未找到其他解决方案.

I added a catch to catch the error. I never found a different solution.

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