LINQ生成不正确的SQL(对不存在的表的引用)

MVC3项目，使用LINQ to Entity和Entity Framework 4 Code First。

在另一篇文章（使用LINQ返回属于列表中所有标签的产品）中，我得到了创建LINQ语句以返回数据子集的帮助。

LINQ在语法上是正确的，可以编译，但生成的SQL不正确。具体来说，它引用了一个不存在的表。如果我更正了表名，它将返回正确的数据，因此LINQ似乎是正确的。

请注意，为了避免这篇长帖子变得更长，我不会发布对象类（Product、Tag和ProductTag），但它们在我之前的问题中列出：使用LINQ 返回属于列表中所有标签的产品

LINQ:

var tags = "administration+commerce"
var tagParams = tags.Split('+').ToList();   //used in linq statement below
_repository.Products.Where(p => tagParams.All(tag => p.Tags.Select(x => x.Name).Contains(tag))).Distinct().Take(75).ToList();   

以下是错误且正确的SQL代码。

不正确的SQL引用了不存在的表

[dbo].[TagProduct] 

以及格式错误的字段

[ExtentN].[Tag_TagId]

如果我将它们更正为"[dbo].[ProductTag]"answers"[ExtentN].[TagId]"，则SQL将正确执行并返回正确的数据。

LINQ生成（且有故障）SQL

SELECT 
[Extent1].[ProductId] AS [ProductId], 
[Extent1].[Name] AS [Name], 
[Extent1].[ShortDescription] AS [ShortDescription], 
[Extent1].[LongDescription] AS [LongDescription], 
[Extent1].[Price] AS [Price]
FROM [dbo].[Product] AS [Extent1]
WHERE  NOT EXISTS (SELECT 
    1 AS [C1]
    FROM  (SELECT 
        N'administration' AS [C1]
        FROM  ( SELECT 1 AS X ) AS [SingleRowTable1]
    UNION ALL
        SELECT 
        N'commerce' AS [C1]
        FROM  ( SELECT 1 AS X ) AS [SingleRowTable2]) AS [UnionAll1]
    WHERE ( NOT EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[TagProduct] AS [Extent2]
        INNER JOIN [dbo].[Tag] AS [Extent3] ON [Extent3].[TagId] = [Extent2].[Tag_TagId]
        WHERE ([Extent1].[ProductId] = [Extent2].[Product_ProductId]) AND ([Extent3].[Name] = [UnionAll1].[C1])
    )) OR (CASE WHEN ( EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[TagProduct] AS [Extent4]
        INNER JOIN [dbo].[Tag] AS [Extent5] ON [Extent5].[TagId] = [Extent4].[Tag_TagId]
        WHERE ([Extent1].[ProductId] = [Extent4].[Product_ProductId]) AND ([Extent5].[Name] = [UnionAll1].[C1])
    )) THEN cast(1 as bit) WHEN ( NOT EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[TagProduct] AS [Extent6]
        INNER JOIN [dbo].[Tag] AS [Extent7] ON [Extent7].[TagId] = [Extent6].[Tag_TagId]
        WHERE ([Extent1].[ProductId] = [Extent6].[Product_ProductId]) AND ([Extent7].[Name] = [UnionAll1].[C1])
    )) THEN cast(0 as bit) END IS NULL)
)

已更正的SQL

SELECT 
[Extent1].[ProductId] AS [ProductId], 
[Extent1].[Name] AS [Name], 
[Extent1].[ShortDescription] AS [ShortDescription], 
[Extent1].[LongDescription] AS [LongDescription], 
[Extent1].[Price] AS [Price]
FROM [dbo].[Product] AS [Extent1]
WHERE  NOT EXISTS (SELECT 
    1 AS [C1]
    FROM  (SELECT 
        N'administration' AS [C1]
        FROM  ( SELECT 1 AS X ) AS [SingleRowTable1]
    UNION ALL
        SELECT 
        N'commerce' AS [C1]
        FROM  ( SELECT 1 AS X ) AS [SingleRowTable2]) AS [UnionAll1]
    WHERE ( NOT EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[ProductTag] AS [Extent2]
        INNER JOIN [dbo].[Tag] AS [Extent3] ON [Extent3].[TagId] = [Extent2].[TagId]
        WHERE ([Extent1].[ProductId] = [Extent2].[ProductId]) AND ([Extent3].[Name] = [UnionAll1].[C1])
    )) OR (CASE WHEN ( EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[ProductTag] AS [Extent4]
        INNER JOIN [dbo].[Tag] AS [Extent5] ON [Extent5].[TagId] = [Extent4].[TagId]
        WHERE ([Extent1].[ProductId] = [Extent4].[ProductId]) AND ([Extent5].[Name] = [UnionAll1].[C1])
    )) THEN cast(1 as bit) WHEN ( NOT EXISTS (SELECT 
        1 AS [C1]
        FROM  [dbo].[ProductTag] AS [Extent6]
        INNER JOIN [dbo].[Tag] AS [Extent7] ON [Extent7].[TagId] = [Extent6].[TagId]
        WHERE ([Extent1].[ProductId] = [Extent6].[ProductId]) AND ([Extent7].[Name] = [UnionAll1].[C1])
    )) THEN cast(0 as bit) END IS NULL)
)

同样，SQL中唯一的更改是

[dbo].[TagProduct] changed to [dbo].[ProductTag]
[ExtentN].[Tag_TagId] changed to [ExtentN].[TagId]

注意，我已经确保数据库中没有名为dbo的对象。TagProduct，并且在我的代码中不存在对TagProduct的引用（也从来没有）。

我的LINQ语句中是否有问题，或者这是LINQ错误？我可以完全废弃它，只创建一个存储过程，但我宁愿找到一个修复方法。

感谢并为这篇冗长的帖子道歉。

编辑

事实证明，问题是一个有缺陷的实体模型，在多对多关系中的表之间存在过多且不必要的导航属性。斯拉马的详细回答是理解发生了什么的关键。

新型号如下：

public class Product
{
    .
    . 
    //public virtual List<Tag> Tags { get; set; }             // <--removed
    public virtual List<ProductTag> ProductTags { get; set; }
}
public class ProductTag
{
    .
    . 
    public virtual Product Product { get; set; }
    public virtual Tag Tag { get; set; }
}
public class Tag
{
    .
    . 
    //public virtual List<Product> Products { get; set; }      // <--removed
    public virtual List<ProductTag> ProductTags { get; set; }
}

public class Tag
{
    public int TagId { get; set; }
    public virtual List<Product> Products { get; set; }         /* 1 */
    public virtual List<ProductTag> ProductTags { get; set; }   /* 2 */
}
public class Product
{
    public int ProductId { get; set; }
    public virtual List<Tag> Tags { get; set; }                 /* 1 */
}
public class ProductTag
{
    public int ProductTagId { get; set; }
    public int ProductId { get; set; }
    public int TagId { get; set; }
    public virtual Product Product { get; set; }                /* 3 */
    public virtual Tag Tag { get; set; }                        /* 2 */
}

modelBuilder.Entity<Product>()
    .HasMany(p => p.Tags)
    .WithMany(t => t.Products)
    .Map(x =>
    {
        x.MapLeftKey("ProductId");
        x.MapRightKey("TagId");
        x.ToTable("ProductTag");
    });