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 p 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 p 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)