--  如何判断数据库是否存在 
 if exists(select * from master.dbo.sysdatabases where name = 'test')
begin
drop database test
print 'test 已经存在,已被删除'
end
else
begin
create database test
on primary
(
  name=test_mdf,
  filename='c:\test.mdf',
  size=10mb,
  maxsize=50mb,
  filegrowth=25%
)
log on
(
  name=test_ldf,
  filename='c:\test.ldf',
  size=10mb,
  maxsize=50mb,
  filegrowth=25%
)
print 'test数据库创建成功'
end