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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