Question

在app中使用从EF代码首次迁移创建的4个视图。此视图中的字段名称相同，类型相同。为了在app的BL中使用这个视图，创建了基类和4个子类。这用于UNION ALL个视图。

父类：

public abstract class CdcBase : EntityBase
{
        public Guid Guid { get; set; }
        public int YearBalance { get; set; }
        public int Typezalezh { get; set; }
        public string License { get; set; }
        public string ObjectName { get; set; }
        public string ZalezhName { get; set; }
        public string PlastName { get; set; }
        public string Category { get; set; }
        public string Parameter { get; set; }
        public string LastVal { get; set; }
        public string Val { get; set; }
        public int Operation { get; set; }
        public DateTime EndT { get; set; }
}

例如，下面是使用view_CDC_1的四个类中的一个：

[Table("view_CDC_1)]
public class CdcResursGas : CdcBase
{
}

在BL中使用repository和Unit Of Work模式。

当我尝试使用以下内容从视图中选择数据时：

var result = _myReposytory.GetAll().ToList();

但是要抓住以下错误：

   InnerException: 
        Class=16
        ErrorCode=-2146232060
        HResult=-2146232060
        LineNumber=4
        Message=Invalid column name 'Id'. Invalid column name 'Id'. Invalid column name 'Id'. Invalid column name 'Id'.
        Number=207
        Procedure=""
        Server=SPB33-IT-W-5557
        Source=.Net SqlClient Data Provider
        State=1
        StackTrace:

EF生成的奇怪查询：

{SELECT 
    CASE WHEN ([UnionAll3].[C1] = 1) THEN '0X0X' WHEN ([UnionAll3].[C2] = 1) THEN '0X1X' WHEN ([UnionAll3].[C3] = 1) THEN '0X2X' ELSE '0X3X' END AS [C1], 
    [UnionAll3].[Id] AS [C2], 
    [Extent5].[Guid] AS [Guid], 
    [Extent5].[YearBalance] AS [YearBalance], 
    [Extent5].[Typezalezh] AS [Typezalezh], 
    [Extent5].[License] AS [License], 
    [Extent5].[ObjectName] AS [ObjectName], 
    [Extent5].[ZalezhName] AS [ZalezhName], 
    [Extent5].[PlastName] AS [PlastName], 
    [Extent5].[Category] AS [Category], 
    [Extent5].[Parameter] AS [Parameter], 
    [Extent5].[LastVal] AS [LastVal], 
    [Extent5].[Val] AS [Val], 
    [Extent5].[Operation] AS [Operation], 
    [Extent5].[EndT] AS [EndT]
    FROM   (SELECT 
        [Extent1].[Id] AS [Id], 
        cast(1 as bit) AS [C1], 
        cast(0 as bit) AS [C2], 
        cast(0 as bit) AS [C3]
        FROM [dbo].[view_1] AS [Extent1]
    UNION ALL
        SELECT 
        [Extent2].[Id] AS [Id], 
        cast(0 as bit) AS [C1], 
        cast(0 as bit) AS [C2], 
        cast(0 as bit) AS [C3]
        FROM [dbo].[view_2] AS [Extent2]
    UNION ALL
        SELECT 
        [Extent3].[Id] AS [Id], 
        cast(0 as bit) AS [C1], 
        cast(1 as bit) AS [C2], 
        cast(0 as bit) AS [C3]
        FROM [dbo].[view_3] AS [Extent3]
    UNION ALL
        SELECT 
        [Extent4].[Id] AS [Id], 
        cast(0 as bit) AS [C1], 
        cast(0 as bit) AS [C2], 
        cast(1 as bit) AS [C3]
        FROM [dbo].[view_4] AS [Extent4]) AS [UnionAll3]
    INNER JOIN [dbo].[CdcBases] AS [Extent5] ON [UnionAll3].[Id] = [Extent5].[Id]}

我不明白为什么在这里cast。我也看到[dbo].[CdcBases]，但数据库没有表CdcBases。但正如我所料，此查询包含视图的UNION ALL。我做错了什么？也许我必须创建4个没有继承并使用LINQ的实体？

如何在EF中继承UNION所有数据库视图？

0 个答案: