SQL查詢內Linq中

SELECT 
    EmployeeType.EmployeeTypeName, EmployeeAttendanceTypes.OverTimeAllowed, 
    EmployeeAttendanceTypes.SundayOffAllowed,     
    EmployeeAttendanceTypes.LeavesAllowed 
FROM 
    EmployeeAttendanceTypes 
INNER JOIN 
    EmployeeType ON EmployeeAttendanceTypes.CompanyId = EmployeeType.CompanyId 
       AND EmployeeAttendanceTypes.EmployeeTypeId = EmployeeType.EmployeeTypeId

加入如何寫這個查詢Linq中的C＃？SQL查詢內Linq中

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2015-11-03 Rana Ali

你不這樣做，至少在精心設計的解決方案。你在你的實體中創建關係，例如。 EmployeeType具有AttendanceTypes集合屬性。在此之後，加載一個EmployeeType也將加載相關AttendanceTypes，無論是熱切（即連接）或懶洋洋地（與單獨的查詢，如果/當你需要他們） –

另一種選擇是將其定義爲一個M-1的關係，也就是說，如果EmployeeType只能有一個AttendanceType，該EmployeeType類將有一個AttendanceType屬性 –

我會與你不評論同意，但它並不總是可能避免。嘗試：

var result = from eat in EmployeeAttaendanceType 
      join et in EmployeeType on 
       new { cId = eat.CompanyId, etId = eat.EmployeeTypeId } 
      equals 
       new { cId = et.CompanyId, etId = et.EmployeeTypeId } 
      select new { 
       EmployeeTypeName = EmployeeType.EmployeeTypeName, 
       OverTimeAllowed = EmployeeAttendanceTypes.OverTimeAllowed,  
       SundayOffAllowed = EmployeeAttendanceTypes.SundayOffAllowed,     
       LeavesAllowed = EmployeeAttendanceTypes.LeavesAllowed 
      }

或者你也可以做到這一點

var result = EmployeeAttendanceType.Join(EmployeeType, 
       eat => new { cId = eat.CompanyId, etId = eat.EmployeeTypeId },   
       et => new { cId = et.CompanyId, etId = et.EmployeeTypeId }, 
       (eat, et) => new { 
        EmployeeTypeName = EmployeeType.EmployeeTypeName, 
        OverTimeAllowed = EmployeeAttendanceTypes.OverTimeAllowed,  
        SundayOffAllowed = EmployeeAttendanceTypes.SundayOffAllowed,     
        LeavesAllowed = EmployeeAttendanceTypes.LeavesAllowed 
       });

這些選擇到匿名類型，但可以選擇到任何物體。

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2015-11-03 16:09:05 Dhunt

SQL查詢內Linq中

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