c# - Entity Framework 从存储过程创建错误的模型

Question

我有一个这样的存储过程“GET_PARTNER”:

SELECT
...
Partners.name AS 'name'  -nvarchar
Partners.city AS 'city'  -nvarchar
NULL AS 'sales'          -money
NULL AS 'comments'       -nvarchar
...

我已将 Entity Framework 6 添加到项目并将其设置为从数据库创建模型，它创建了一个模型“GET_PARTNER_Result”，如下所示:

    //------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated from a template.
//
//     Manual changes to this file may cause unexpected behavior in your application.
//     Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
namespace WSExport.Model
{
using System;

public partial class GET_PARTNER_Result
{
   public string name {get; set;}
   public string city {get; set;}
   public Nullable<int> sales {get; set;}    -wrong datatype
   public Nullable<int> comments {get; set;} -wrong datatype
}
}

如何修改存储过程，或者是否可以配置 ef 以创建具有正确数据类型的模型？像这样:

public Nullable<decimal> sales {get; set;}
public string comments {get; set;}

Answer 1

默认情况下 NULL 是 INT 数据类型。使用 CAST:

SELECT
...
Partners.name AS name                       --nvarchar
,Partners.city AS city                      --nvarchar
,CAST(NULL AS MONEY) AS sales               --money
,CAST(NULL AS NVARCHAR(1000)) AS comments   --nvarchar

快速检查元数据:

SELECT name, system_type_name
FROM sys.dm_exec_describe_first_result_set(N'SELECT NULL AS c', NULL, 0)

Rextester DEMO

您还可以使用以下方法检查整个存储过程的元数据:

SELECT name, system_type_name
FROM sys.dm_exec_describe_first_result_set(N'EXEC GET_PARTNER params..', NULL, 0)