替换SQLServer数据库中所有表的所有字段的某些内容--方法一

exec sp_msforeachtable @command1=N' 
 declare @s nvarchar(4000),@tbname sysname 
 select @s=N'''',@tbname=N''?'' 
 select @s=@s+N'',''+quotename(a.name)+N''=replace(''+quotename(a.name)+N'',N''''aa'''',N''''bb'''')'' 
 from syscolumns a,systypes b 
 where a.id=object_id(@tbname) 
 and a.xusertype=b.xusertype 
 and b.name like N''%char'' 
 if @@rowcount>0 
 begin 
 set @s=stuff(@s,1,1,N'''') 
 exec(N''update ''+@tbname+'' set ''+@s) 
 end'