Linq in条件查询

时间:2023-02-27 08:29:17

Linq 实现sql中的not in和in条件查询

T-SQL的IN:

Select ProductID, ProductName, CategoryID
From dbo.Products
Where CategoryID in (1, 2)

  

T-SQL的NOT IN:

Select ProductID, ProductName, CategoryID
From dbo.Products
Where CategoryID not in (1, 2)

  

Or

Select ProductID, ProductName, CategoryID
From dbo.Products
Where not CategoryID in (1, 2)

  

LINQ的IN:

var queryResult = from in db.Products
where (new int?[] {1,2}).Contains(p.CategoryID)
select p;

  

LINQ的IN解析成SQL:

SELECT [t0].[ProductID], [t0].[ProductName], [t0].[SupplierID], [t0].[CategoryID], [t0].[QuantityPerUnit], [t0].[UnitPrice], [t0].[UnitsInStock], [t0].[UnitsOnOrder], [t0].[ReorderLevel], [t0].[Discontinued]
FROM [dbo].[Products]AS [t0]
WHERE [t0].[CategoryID] IN (@p0, @p1)

  

LINQ的NOT IN:

var queryResult = from in db.Products
where ! (new int?[] {1,2}).Contains(p.CategoryID)
select p;

  

LINQ的NOT IN解析成SQL:

SELECT [t0].[ProductID], [t0].[ProductName], [t0].[SupplierID], [t0].[CategoryID], [t0].[QuantityPerUnit], [t0].[UnitPrice], [t0].[UnitsInStock], [t0].[UnitsOnOrder], [t0].[ReorderLevel], [t0].[Discontinued]
FROM [dbo].[Products]AS [t0]
WHERE NOT [t0].[CategoryID] IN (@p0, @p1)