IF EXISTS (SELECT * FROM sys.check_constraints WHERE object_id = OBJECT_ID(N'[dbo].[CK_tbl_Test]') AND parent_object_id = OBJECT_ID(N'[dbo].[tbl_Test]')) ALTER TABLE [dbo].[tbl_Test] DROP CONSTRAINT [CK_tbl_Test] GOUSE [CodeRobotDB] GO/****** Object: Table [dbo].[tbl_Test] Script Date: 08/31/2014 22:14:35 ******/ IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[tbl_Test]') AND type in (N'U')) DROP TABLE [dbo].[tbl_Test] GOUSE [CodeRobotDB] GO/****** Object: Table [dbo].[tbl_Test] Script Date: 08/31/2014 22:14:35 ******/ SET ANSI_NULLS ON GOSET QUOTED_IDENTIFIER ON GOSET ANSI_PADDING ON GOCREATE TABLE [dbo].[tbl_Test]( [UID] [varchar](20) NOT NULL, [PWD] [varchar](30) NOT NULL ) ON [PRIMARY]GOSET ANSI_PADDING OFF GOALTER TABLE [dbo].[tbl_Test] WITH CHECK ADD CONSTRAINT [CK_tbl_Test] CHECK ((len([pwd])>=(6))) GOALTER TABLE [dbo].[tbl_Test] CHECK CONSTRAINT [CK_tbl_Test] GO
IF EXISTS (SELECT * FROM sys.check_constraints WHERE object_id = OBJECT_ID(N'[dbo].[CK_tbl_Test]') AND parent_object_id = OBJECT_ID(N'[dbo].[tbl_Test]'))
ALTER TABLE [dbo].[tbl_Test] DROP CONSTRAINT [CK_tbl_Test]
GOUSE [CodeRobotDB]
GO/****** Object: Table [dbo].[tbl_Test] Script Date: 08/31/2014 22:14:35 ******/
IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[tbl_Test]') AND type in (N'U'))
DROP TABLE [dbo].[tbl_Test]
GOUSE [CodeRobotDB]
GO/****** Object: Table [dbo].[tbl_Test] Script Date: 08/31/2014 22:14:35 ******/
SET ANSI_NULLS ON
GOSET QUOTED_IDENTIFIER ON
GOSET ANSI_PADDING ON
GOCREATE TABLE [dbo].[tbl_Test](
[UID] [varchar](20) NOT NULL,
[PWD] [varchar](30) NOT NULL
) ON [PRIMARY]GOSET ANSI_PADDING OFF
GOALTER TABLE [dbo].[tbl_Test] WITH CHECK ADD CONSTRAINT [CK_tbl_Test] CHECK ((len([pwd])>=(6)))
GOALTER TABLE [dbo].[tbl_Test] CHECK CONSTRAINT [CK_tbl_Test]
GO
打开查询分析器==>右键你的表名==>设计==>选中你的密码字段==>点击上面快捷按钮【管理check约束】==>弹出界面中点击添加按钮==>点击【表达式】==>输入len(pwd)>=6==>确定后保存即可