摘要： 我们知道在SQL中一共有五种JOIN操作：INNER JOIN、LEFT OUTER JOIN、RIGHT OUTER JOIN、FULL OUTER JOIN、CROSS JOIN1>先创建两个表Group、User，两表的关系是N:NCREATE TABLE [dbo].[Group]( [Id] [int] IDENTITY(1,1) NOT NULL, [GroupName] [nvarchar](50) NULL, CONSTRAINT [PK_Group] PRIMARY KEY CLUSTERED ( [Id] ASC ... 阅读全文