if exists (select * from sys.databases where name = '數據庫名') ?
? drop database [數據庫名]

if exists (select * from sysobjects where id = object_id(N'[表名]') and OBJECTPROPERTY(id, N'IsUserTable') = 1) ?
? drop table [表名]

if exists (select * from sysobjects where id = object_id(N'[存儲過程名]') and OBJECTPROPERTY(id, N'IsProcedure') = 1) ?
? drop procedure [存儲過程名]

if object_id('tempdb..#臨時表名') is not null ? ?
? drop table #臨時表名

--SQL Server 2000 ??
IF EXISTS (SELECT * FROM sysviews WHERE object_id = '[dbo].[視圖名]' ?
--SQL Server 2005 ??
IF EXISTS (SELECT * FROM sys.views WHERE object_id = '[dbo].[視圖名]' ?--SQL Server 2000
IF EXISTS (SELECT * FROM sysviews WHERE object_id = '[dbo].[視圖名]'
--SQL Server 2005
IF EXISTS (SELECT * FROM sys.views WHERE object_id = '[dbo].[視圖名]'

-- ?判斷要創建的函數名是否存在 ? ?
? if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[函數名]') and xtype in (N'FN', N'IF', N'TF')) ? ?
? drop function [dbo].[函數名] ? ?-- ?判斷要創建的函數名是否存在 ?

SELECT [name],[id],crdate FROM sysobjects where xtype='U' ?
/* ?
xtype 的表示參數類型，通常包括如下這些 ?
C = CHECK 約束 ?
D = 默認值或 DEFAULT 約束 ?
F = FOREIGN KEY 約束 ?
L = 日志 ?
FN = 標量函數 ?
IF = 內嵌表函數 ?
P = 存儲過程 ?
PK = PRIMARY KEY 約束（類型是 K） ?
RF = 復制篩選存儲過程 ?
S = 系統表 ?
TF = 表函數 ?
TR = 觸發器 ?
U = 用戶表 ?
UQ = UNIQUE 約束（類型是 K） ?
V = 視圖 ?
X = 擴展存儲過程*/

if exists(select * from syscolumns where id=object_id('表名') and name='列名') ?
? alter table 表名 drop column 列名

if columnproperty(object_id('table'),'col','IsIdentity')=1 ?
? print '自增列' ?
else ?
? print '不是自增列' ?

if exists(select * from sysindexes where id=object_id('表名') and name='索引名') ? ?
? print ?'存在' ? ?
else ? ?
? print ?'不存在11 查看數據庫中對象
SELECT * FROM sys.sysobjects WHERE name='對象名'