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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[align=center]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[/align]

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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