做统计或运算时报 DbArithmeticExpression arguments must have a numeric common type

问题描述

使用Linq语句做统计或运算时总是提示DbArithmeticExpressionargumentsmusthaveanumericcommontype，要有个常见的参数类型，表中有二个时间字段使用fromainDbContent.tableNameselectnewt{Length=(a.EndTime-a.StartTime).Days}会出现以上异常，类t中的Length是int类型。(fromainDbContent.tableNameselectnew{Length=(a.EndTime-a.StartTime).Days}).Sum();使用Sum也是同样报错

解决方案

解决方案二：
YouwouldwanttouseSqlFunctions.DateDiff:https://msdn.microsoft.com/en-us/library/dd487052(v=vs.110).aspxfromainDbContent.tableNameselectnewt{Length=SqlFunctions.DateDiff("day",a.StartTime,a.EndTime)}