EF4如何调用标量UDF [英] EF4 how to call a scalar UDF

问题描述

我想从实体框架调用标量UDF在SQL Server中。它显示了在存储部分的模型浏览器。

任何帮助表示赞赏。

  //在EDMX文件时，它在存储模型
 
将显示出来;功能名称=GetPerformanceIndicator的返回类型=浮动集合=false的内置=假NiladicFunction =假IsComposable =真ParameterTypeSemantics =AllowImplicitConversion架构=DBO> 
<参数名称=INVTYPE =INT模式=在/> 
<参数名称=基金TYPE =INT模式=在/> 
<参数名称=电流TYPE =INT模式=在/> 
< /功能> 
< /模式>< / EDMX：StorageModels> 
 
 //在代码我想在论坛http://social.msdn.microsoft.com/Forums/en-US/adodotnetentityframework/thread/92a3214b-a662-44d5提到调用-bed3-11eae9926be6 / 
 VAR的查询= _context.CreateQuery<双>（IRISModel.Store.GetPerformanceIndicator（@curr，@fund，@inv），
新System.Data.Objects.ObjectParameter（ INV，invfund.Investors.Investor_ID），
新System.Data.Objects.ObjectParameter（基金，invfund.Funds.Fund_ID），
新System.Data.Objects.ObjectParameter（电流invfund.Currency.Currency_ID））; 
 
 VAR X2 = query.Execute（System.Data.Objects.MergeOption.NoTracking）; 
 
 X = x2.FirstOrDefault（）; //<<  - 这总是返回零
  

解决方案

您是否尝试过这种做法？注意使用 [EdmFunction] 属性来调用您的自定义功能提供了钩EF

I am trying to call a scalar UDF in SQL Server from the entity framework. It shows up in the the model browser in the Store section.

Any help is Appreciated..

 //In the EDMX File it shows up in the storage model

<Function Name="GetPerformanceIndicator" ReturnType="float" Aggregate="false" BuiltIn="false" NiladicFunction="false" IsComposable="true" ParameterTypeSemantics="AllowImplicitConversion" Schema="dbo">
          <Parameter Name="inv" Type="int" Mode="In" />
          <Parameter Name="fund" Type="int" Mode="In" />
          <Parameter Name="curr" Type="int" Mode="In" />
        </Function>
      </Schema></edmx:StorageModels>

// In the Code I am trying to call as mentioned in the Forum http://social.msdn.microsoft.com/Forums/en-US/adodotnetentityframework/thread/92a3214b-a662-44d5-bed3-11eae9926be6/
var query = _context.CreateQuery<double>("IRISModel.Store.GetPerformanceIndicator(@curr, @fund, @inv)",
                        new System.Data.Objects.ObjectParameter("inv", invfund.Investors.Investor_ID),
                        new System.Data.Objects.ObjectParameter("fund", invfund.Funds.Fund_ID),
                       new System.Data.Objects.ObjectParameter("curr", invfund.Currency.Currency_ID));

                    var x2 = query.Execute(System.Data.Objects.MergeOption.NoTracking);

                    x = x2.FirstOrDefault(); //<<-- This always return zero

解决方案

Have you tried this approach? Note the use of an [EdmFunction] attribute to provide the hook to EF for calling your custom function.

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