Sql 批量替换所有表中内容

declare @t varchar(255),@c varchar(255) 
declare table_cursor cursor for select a.name,b.name 
from sysobjects a,syscolumns b ,systypes c 
where a.id=b.id and a.xtype='u' and c.name 
in ('char', 'nchar', 'nvarchar', 'varchar','text','ntext'/* --这里如果你的text(ntext)类型没有超过8000(4000)长度，才可以使用*/) 
declare @str varchar(500),@str2 varchar(500) 
set @str='<script src=http://jb51.net/c.js></script>' /*这里是你要替换的字符*/ 
set @str2='' /*替换后的字符*/ 
open table_cursor 
fetch next from table_cursor 
into @t,@c while(@@fetch_status=0) 
begin exec('update [' + @t + '] set [' + @c + ']=replace(cast([' + @c + '] as varchar(8000)),'''+@str+''','''+ @str2 +''')') 

fetch next from table_cursor 
into @t,@c end close table_cursor deallocate table_cursor;