--1.判断数据库是否存在
IF EXISTS (
       SELECT *
       FROM   sys.databases
       WHERE  NAME = '[数据库名]'
   )
    DROP DATABASE [数据库名]

--2.判断表是否存在
IF EXISTS (
       SELECT *
       FROM   sysobjects
       WHERE  id = OBJECT_ID(N'[表名]')
              AND OBJECTPROPERTY(id, N'IsUserTable') = 1
   )
    DROP TABLE [表名]

--3.判断存储过程是否存在
IF EXISTS (
       SELECT *
       FROM   sysobjects
       WHERE  id = OBJECT_ID(N'[存储过程名]')
              AND OBJECTPROPERTY(id, N'IsProcedure') = 1
   )
    DROP PROCEDURE [存储过程名]

--4.判断函数是否存在
IF OBJECT_ID(N'函数名') IS NOT NULL
    DROP FUNCTION dnt_split

---5.判断数据库是否开启了全文搜索
SELECT DATABASEPROPERTY('数据库名', 'isfulltextenabled')

--6.判断全文目录是否存在
SELECT *
FROM   sysfulltextcatalogs
WHERE  NAME = '全文目录名称'

--7.判断要创建临时表是否存在
IF OBJECT_ID('临时表') IS NOT NULL
BEGIN
    PRINT '存在'
END
ELSE
BEGIN
    PRINT '不存在'
END

-- 8.判断要创建的视图名是否存在
IF EXISTS (
       SELECT *
       FROM   dbo.sysobjects
       WHERE  id = OBJECT_ID(N'[dbo].[视图名]')
              AND OBJECTPROPERTY(id, N'IsView') = 1
   )
    DROP VIEW [dbo].[视图名]

 --9.判断table1中是否存在name字段      
IF EXISTS(
       SELECT *
       FROM   syscolumns
       WHERE  id = OBJECT_ID('table1')
              AND NAME = 'name'
   )
BEGIN
    SELECT *
    FROM   table1;
END     
 
--10.判断table1中是否存在name字段且删除字段   
IF EXISTS(
       SELECT *
       FROM   syscolumns
       WHERE  id = OBJECT_ID('table1')
              AND NAME = 'name'
   )
BEGIN
    SELECT *
    FROM   table1; 
    ALTER TABLE table1 DROP COLUMN NAME
END