再接再厉VS 2008 sp1 + .NET 3.5 sp1(2) - Entity Framework(实体框架)之详解 Linq To Entities 之一

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再接再厉VS 2008 sp1 + .NET 3.5 sp1(2) - Entity Framework(实体框架)之详解 Linq To Entities 之一

作者： webabcd


介绍
以Northwind为示例数据库，ADO.NET Entity Framework之Linq To Entities

• First - 返回集合中的第一个成员；不延迟
• FirstOrDefault - 返回集合中的第一个成员（找不到则返回null）；不延迟
• All - 是否集合中所有成员都满足某一条件；不延迟
• Any - 集合中是否有成员满足某一条件；不延迟
• Average - 取平均值；不延迟
• Sum - 求和；不延迟
• Max - 取最大值；不延迟
• Min - 取最小值；不延迟
• Count - 取指定集合的成员数，返回值类型int；不延迟
• LongCount - 取指定集合的成员数，返回值类型long；不延迟
• Take - 获取集合的前 n 个成员；延迟
• Skip - 跳过集合的前 n 个成员；延迟（Linq To Entities 需要先排序才能 Skip）
• Distinct - 过滤集合中的相同项；延迟
• Union - 连接不同集合，自动过滤相同项；延迟
• UnionAll - 连接不同集合，不会自动过滤相同项；延迟
• Concat - 连接不同集合，不会自动过滤相同项；延迟
• Intersect - 获取不同集合的相同项（交集）；延迟
• Except - 从某集合中删除其与另一个集合中相同的项；延迟

示例
First

using (var ctx = new NorthwindEntities())
{
        Products first = ctx.Products.First(p => p.ProductID > 3);
}
SELECT    
[Limit1].[C1] AS [C1],    
[Limit1].[Discontinued] AS [Discontinued],    
[Limit1].[ProductID] AS [ProductID],    
[Limit1].[ProductName] AS [ProductName],    
[Limit1].[QuantityPerUnit] AS [QuantityPerUnit],    
[Limit1].[ReorderLevel] AS [ReorderLevel],    
[Limit1].[UnitPrice] AS [UnitPrice],    
[Limit1].[UnitsInStock] AS [UnitsInStock],    
[Limit1].[UnitsOnOrder] AS [UnitsOnOrder],    
[Limit1].[CategoryID] AS [CategoryID],    
[Limit1].[SupplierID] AS [SupplierID]
FROM ( SELECT TOP (1)    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[SupplierID] AS [SupplierID],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        1 AS [C1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE [Extent1].[ProductID] > 3
)     AS [Limit1]

 

FirstOrDefault

using (var ctx = new NorthwindEntities())
{
        Products firstOrDefault = ctx.Products.FirstOrDefault(p => p.ProductID > 100);
}
SELECT    
[Limit1].[C1] AS [C1],    
[Limit1].[Discontinued] AS [Discontinued],    
[Limit1].[ProductID] AS [ProductID],    
[Limit1].[ProductName] AS [ProductName],    
[Limit1].[QuantityPerUnit] AS [QuantityPerUnit],    
[Limit1].[ReorderLevel] AS [ReorderLevel],    
[Limit1].[UnitPrice] AS [UnitPrice],    
[Limit1].[UnitsInStock] AS [UnitsInStock],    
[Limit1].[UnitsOnOrder] AS [UnitsOnOrder],    
[Limit1].[CategoryID] AS [CategoryID],    
[Limit1].[SupplierID] AS [SupplierID]
FROM ( SELECT TOP (1)    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[SupplierID] AS [SupplierID],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        1 AS [C1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE [Extent1].[ProductID] > 100
)     AS [Limit1]

 

All

using (var ctx = new NorthwindEntities())
{
        bool all = ctx.Products.All(p => p.ProductID > 3);
}
SELECT    
CASE WHEN ( NOT EXISTS ( SELECT    
        cast(1 as bit) AS [C1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE ( NOT ([Extent1].[ProductID] > 3)) OR ( CASE WHEN ([Extent1].[ProductID] > 3) THEN cast(1 as bit) WHEN ( NOT ([Extent1].[ProductID] > 3)) THEN cast(0 as bit) END IS NULL)
)) THEN cast(1 as bit) WHEN ( EXISTS ( SELECT    
        cast(1 as bit) AS [C1]
        FROM [dbo].[Products] AS [Extent2]
        WHERE ( NOT ([Extent2].[ProductID] > 3)) OR ( CASE WHEN ([Extent2].[ProductID] > 3) THEN cast(1 as bit) WHEN ( NOT ([Extent2].[ProductID] > 3)) THEN cast(0 as bit) END IS NULL)
)) THEN cast(0 as bit) END AS [C1]
FROM    ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]

 

Any

using (var ctx = new NorthwindEntities())
{
        bool any = ctx.Products.Any(p => p.ProductID > 3);
}
SELECT    
CASE WHEN ( EXISTS ( SELECT    
        cast(1 as bit) AS [C1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE [Extent1].[ProductID] > 3
)) THEN cast(1 as bit) WHEN ( NOT EXISTS ( SELECT    
        cast(1 as bit) AS [C1]
        FROM [dbo].[Products] AS [Extent2]
        WHERE [Extent2].[ProductID] > 3
)) THEN cast(0 as bit) END AS [C1]
FROM    ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]

 

Average

using (var ctx = new NorthwindEntities())
{
        decimal? average = ctx.Products.Average(p => p.UnitPrice);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        AVG([Extent1].[UnitPrice]) AS [A1]
        FROM [dbo].[Products] AS [Extent1] ) AS [GroupBy1] ON 1 = 1

 

Sum

using (var ctx = new NorthwindEntities())
{
        decimal? sum = ctx.Products.Sum(p => p.UnitPrice);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        SUM([Extent1].[UnitPrice]) AS [A1]
        FROM [dbo].[Products] AS [Extent1] ) AS [GroupBy1] ON 1 = 1

 

Max

using (var ctx = new NorthwindEntities())
{
        decimal? max = ctx.Products.Max(p => p.UnitPrice);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        MAX([Extent1].[UnitPrice]) AS [A1]
        FROM [dbo].[Products] AS [Extent1] ) AS [GroupBy1] ON 1 = 1

 

Min

using (var ctx = new NorthwindEntities())
{
        decimal? min = ctx.Products.Min(p => p.UnitPrice);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        MIN([Extent1].[UnitPrice]) AS [A1]
        FROM [dbo].[Products] AS [Extent1] ) AS [GroupBy1] ON 1 = 1

 

Count

using (var ctx = new NorthwindEntities())
{
        int count = ctx.Products.Count(p => p.ProductID > 3);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        COUNT(cast(1 as bit)) AS [A1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE [Extent1].[ProductID] > 3 ) AS [GroupBy1] ON 1 = 1

 

LongCount

using (var ctx = new NorthwindEntities())
{
        long longCount = ctx.Products.LongCount(p => p.ProductID > 3);
}
SELECT    
[GroupBy1].[A1] AS [C1]
FROM     ( SELECT cast(1 as bit) AS X ) AS [SingleRowTable1]
LEFT OUTER JOIN    ( SELECT    
        COUNT_BIG(cast(1 as bit)) AS [A1]
        FROM [dbo].[Products] AS [Extent1]
        WHERE [Extent1].[ProductID] > 3 ) AS [GroupBy1] ON 1 = 1

 

Take

using (var ctx = new NorthwindEntities())
{
        IQueryable<Products> take = ctx.Products.Take(3);
        take.ToList();
}
SELECT    
[Limit1].[C1] AS [C1],    
[Limit1].[Discontinued] AS [Discontinued],    
[Limit1].[ProductID] AS [ProductID],    
[Limit1].[ProductName] AS [ProductName],    
[Limit1].[QuantityPerUnit] AS [QuantityPerUnit],    
[Limit1].[ReorderLevel] AS [ReorderLevel],    
[Limit1].[UnitPrice] AS [UnitPrice],    
[Limit1].[UnitsInStock] AS [UnitsInStock],    
[Limit1].[UnitsOnOrder] AS [UnitsOnOrder],    
[Limit1].[CategoryID] AS [CategoryID],    
[Limit1].[SupplierID] AS [SupplierID]
FROM ( SELECT TOP (3)    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[SupplierID] AS [SupplierID],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        1 AS [C1]
        FROM [dbo].[Products] AS [Extent1]
)     AS [Limit1]

 

Skip

using (var ctx = new NorthwindEntities())
{
        IQueryable<Products> skip = ctx.Products.OrderBy(p => p.UnitPrice).Skip(3);
        skip.ToList();
}
SELECT    
[Project1].[C1] AS [C1],    
[Project1].[Discontinued] AS [Discontinued],    
[Project1].[ProductID] AS [ProductID],    
[Project1].[ProductName] AS [ProductName],    
[Project1].[QuantityPerUnit] AS [QuantityPerUnit],    
[Project1].[ReorderLevel] AS [ReorderLevel],    
[Project1].[UnitPrice] AS [UnitPrice],    
[Project1].[UnitsInStock] AS [UnitsInStock],    
[Project1].[UnitsOnOrder] AS [UnitsOnOrder],    
[Project1].[CategoryID] AS [CategoryID],    
[Project1].[SupplierID] AS [SupplierID]
FROM ( SELECT [Project1].[CategoryID] AS [CategoryID], [Project1].[Discontinued] AS [Discontinued], [Project1].[ProductID] AS [ProductID], [Project1].[ProductName] AS [ProductName], [Project1].[QuantityPerUnit] AS [QuantityPerUnit], [Project1].[ReorderLevel] AS [ReorderLevel], [Project1].[SupplierID] AS [SupplierID], [Project1].[UnitPrice] AS [UnitPrice], [Project1].[UnitsInStock] AS [UnitsInStock], [Project1].[UnitsOnOrder] AS [UnitsOnOrder], [Project1].[C1] AS [C1], row_number() OVER (ORDER BY [Project1].[UnitPrice] ASC) AS [row_number]
        FROM ( SELECT    
                [Extent1].[CategoryID] AS [CategoryID],    
                [Extent1].[Discontinued] AS [Discontinued],    
                [Extent1].[ProductID] AS [ProductID],    
                [Extent1].[ProductName] AS [ProductName],    
                [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
                [Extent1].[ReorderLevel] AS [ReorderLevel],    
                [Extent1].[SupplierID] AS [SupplierID],    
                [Extent1].[UnitPrice] AS [UnitPrice],    
                [Extent1].[UnitsInStock] AS [UnitsInStock],    
                [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
                1 AS [C1]
                FROM [dbo].[Products] AS [Extent1]
        )     AS [Project1]
)     AS [Project1]
WHERE [Project1].[row_number] > 3
ORDER BY [Project1].[UnitPrice] ASC

 

Distinct 

using (var ctx = new NorthwindEntities())
{
        ObjectQuery<Products> distinct = ctx.Products.Distinct();
        distinct.ToList();
}
SELECT    
1 AS [C1],    
[Extent1].[Discontinued] AS [Discontinued],    
[Extent1].[ProductID] AS [ProductID],    
[Extent1].[ProductName] AS [ProductName],    
[Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
[Extent1].[ReorderLevel] AS [ReorderLevel],    
[Extent1].[UnitPrice] AS [UnitPrice],    
[Extent1].[UnitsInStock] AS [UnitsInStock],    
[Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
[Extent1].[CategoryID] AS [CategoryID],    
[Extent1].[SupplierID] AS [SupplierID]
FROM [dbo].[Products] AS [Extent1]

 

Union

using (var ctx = new NorthwindEntities())
{
        ObjectQuery<Products> union = ctx.Products.Union(ctx.Products);
        union.ToList();
}
SELECT    
1 AS [C1],    
[Distinct1].[C1] AS [C2],    
[Distinct1].[C2] AS [C3],    
[Distinct1].[C3] AS [C4],    
[Distinct1].[C4] AS [C5],    
[Distinct1].[C5] AS [C6],    
[Distinct1].[C6] AS [C7],    
[Distinct1].[C7] AS [C8],    
[Distinct1].[C8] AS [C9],    
[Distinct1].[C9] AS [C10],    
[Distinct1].[C10] AS [C11]
FROM ( SELECT DISTINCT    
        [UnionAll1].[Discontinued] AS [C1],    
        [UnionAll1].[ProductID] AS [C2],    
        [UnionAll1].[ProductName] AS [C3],    
        [UnionAll1].[QuantityPerUnit] AS [C4],    
        [UnionAll1].[ReorderLevel] AS [C5],    
        [UnionAll1].[UnitPrice] AS [C6],    
        [UnionAll1].[UnitsInStock] AS [C7],    
        [UnionAll1].[UnitsOnOrder] AS [C8],    
        [UnionAll1].[CategoryID] AS [C9],    
        [UnionAll1].[SupplierID] AS [C10]
        FROM    ( SELECT    
                [Extent1].[Discontinued] AS [Discontinued],    
                [Extent1].[ProductID] AS [ProductID],    
                [Extent1].[ProductName] AS [ProductName],    
                [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
                [Extent1].[ReorderLevel] AS [ReorderLevel],    
                [Extent1].[UnitPrice] AS [UnitPrice],    
                [Extent1].[UnitsInStock] AS [UnitsInStock],    
                [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
                [Extent1].[CategoryID] AS [CategoryID],    
                [Extent1].[SupplierID] AS [SupplierID]
                FROM [dbo].[Products] AS [Extent1]
        UNION ALL
                 SELECT    
                [Extent2].[Discontinued] AS [Discontinued],    
                [Extent2].[ProductID] AS [ProductID],    
                [Extent2].[ProductName] AS [ProductName],    
                [Extent2].[QuantityPerUnit] AS [QuantityPerUnit],    
                [Extent2].[ReorderLevel] AS [ReorderLevel],    
                [Extent2].[UnitPrice] AS [UnitPrice],    
                [Extent2].[UnitsInStock] AS [UnitsInStock],    
                [Extent2].[UnitsOnOrder] AS [UnitsOnOrder],    
                [Extent2].[CategoryID] AS [CategoryID],    
                [Extent2].[SupplierID] AS [SupplierID]
                FROM [dbo].[Products] AS [Extent2]) AS [UnionAll1]
)     AS [Distinct1]

 

UnionAll

using (var ctx = new NorthwindEntities())
{
        ObjectQuery<Products> unionAll = ctx.Products.UnionAll(ctx.Products);
        unionAll.ToList();
}
SELECT    
1 AS [C1],    
[UnionAll1].[Discontinued] AS [C2],    
[UnionAll1].[ProductID] AS [C3],    
[UnionAll1].[ProductName] AS [C4],    
[UnionAll1].[QuantityPerUnit] AS [C5],    
[UnionAll1].[ReorderLevel] AS [C6],    
[UnionAll1].[UnitPrice] AS [C7],    
[UnionAll1].[UnitsInStock] AS [C8],    
[UnionAll1].[UnitsOnOrder] AS [C9],    
[UnionAll1].[CategoryID] AS [C10],    
[UnionAll1].[SupplierID] AS [C11]
FROM    ( SELECT    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent1]
UNION ALL
         SELECT    
        [Extent2].[Discontinued] AS [Discontinued],    
        [Extent2].[ProductID] AS [ProductID],    
        [Extent2].[ProductName] AS [ProductName],    
        [Extent2].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent2].[ReorderLevel] AS [ReorderLevel],    
        [Extent2].[UnitPrice] AS [UnitPrice],    
        [Extent2].[UnitsInStock] AS [UnitsInStock],    
        [Extent2].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent2].[CategoryID] AS [CategoryID],    
        [Extent2].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent2]) AS [UnionAll1]

 

Concat

using (var ctx = new NorthwindEntities())
{
        IQueryable<Products> concat = ctx.Products.Concat(ctx.Products);
        concat.ToList();
}
SELECT    
1 AS [C1],    
[UnionAll1].[Discontinued] AS [C2],    
[UnionAll1].[ProductID] AS [C3],    
[UnionAll1].[ProductName] AS [C4],    
[UnionAll1].[QuantityPerUnit] AS [C5],    
[UnionAll1].[ReorderLevel] AS [C6],    
[UnionAll1].[UnitPrice] AS [C7],    
[UnionAll1].[UnitsInStock] AS [C8],    
[UnionAll1].[UnitsOnOrder] AS [C9],    
[UnionAll1].[CategoryID] AS [C10],    
[UnionAll1].[SupplierID] AS [C11]
FROM    ( SELECT    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent1]
UNION ALL
         SELECT    
        [Extent2].[Discontinued] AS [Discontinued],    
        [Extent2].[ProductID] AS [ProductID],    
        [Extent2].[ProductName] AS [ProductName],    
        [Extent2].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent2].[ReorderLevel] AS [ReorderLevel],    
        [Extent2].[UnitPrice] AS [UnitPrice],    
        [Extent2].[UnitsInStock] AS [UnitsInStock],    
        [Extent2].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent2].[CategoryID] AS [CategoryID],    
        [Extent2].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent2]) AS [UnionAll1]

 

Intersect

using (var ctx = new NorthwindEntities())
{
        ObjectQuery<Products> intersect = ctx.Products.Intersect(ctx.Products);
        intersect.ToList();
}
SELECT    
1 AS [C1],    
[Intersect1].[Discontinued] AS [C2],    
[Intersect1].[ProductID] AS [C3],    
[Intersect1].[ProductName] AS [C4],    
[Intersect1].[QuantityPerUnit] AS [C5],    
[Intersect1].[ReorderLevel] AS [C6],    
[Intersect1].[UnitPrice] AS [C7],    
[Intersect1].[UnitsInStock] AS [C8],    
[Intersect1].[UnitsOnOrder] AS [C9],    
[Intersect1].[CategoryID] AS [C10],    
[Intersect1].[SupplierID] AS [C11]
FROM    ( SELECT    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent1]
INTERSECT
         SELECT    
        [Extent2].[Discontinued] AS [Discontinued],    
        [Extent2].[ProductID] AS [ProductID],    
        [Extent2].[ProductName] AS [ProductName],    
        [Extent2].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent2].[ReorderLevel] AS [ReorderLevel],    
        [Extent2].[UnitPrice] AS [UnitPrice],    
        [Extent2].[UnitsInStock] AS [UnitsInStock],    
        [Extent2].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent2].[CategoryID] AS [CategoryID],    
        [Extent2].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent2]) AS [Intersect1]

 

Except

using (var ctx = new NorthwindEntities())
{
        ObjectQuery<Products> except = ctx.Products.Except(ctx.Products);
        except.ToList();
}
SELECT    
1 AS [C1],    
[Except1].[Discontinued] AS [C2],    
[Except1].[ProductID] AS [C3],    
[Except1].[ProductName] AS [C4],    
[Except1].[QuantityPerUnit] AS [C5],    
[Except1].[ReorderLevel] AS [C6],    
[Except1].[UnitPrice] AS [C7],    
[Except1].[UnitsInStock] AS [C8],    
[Except1].[UnitsOnOrder] AS [C9],    
[Except1].[CategoryID] AS [C10],    
[Except1].[SupplierID] AS [C11]
FROM    ( SELECT    
        [Extent1].[Discontinued] AS [Discontinued],    
        [Extent1].[ProductID] AS [ProductID],    
        [Extent1].[ProductName] AS [ProductName],    
        [Extent1].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent1].[ReorderLevel] AS [ReorderLevel],    
        [Extent1].[UnitPrice] AS [UnitPrice],    
        [Extent1].[UnitsInStock] AS [UnitsInStock],    
        [Extent1].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent1].[CategoryID] AS [CategoryID],    
        [Extent1].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent1]
EXCEPT
         SELECT    
        [Extent2].[Discontinued] AS [Discontinued],    
        [Extent2].[ProductID] AS [ProductID],    
        [Extent2].[ProductName] AS [ProductName],    
        [Extent2].[QuantityPerUnit] AS [QuantityPerUnit],    
        [Extent2].[ReorderLevel] AS [ReorderLevel],    
        [Extent2].[UnitPrice] AS [UnitPrice],    
        [Extent2].[UnitsInStock] AS [UnitsInStock],    
        [Extent2].[UnitsOnOrder] AS [UnitsOnOrder],    
        [Extent2].[CategoryID] AS [CategoryID],    
        [Extent2].[SupplierID] AS [SupplierID]
        FROM [dbo].[Products] AS [Extent2]) AS [Except1]

 

 

OK
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