记录容易忘记的方法

SELECT ID, Name, CategoryID
FROM TableName AS a
WHERE (ID IN
          (SELECT TOP (n) ID
         FROM TableName AS b
         WHERE (a.CategoryID = CategoryID)))

USE master
Go
ALTER DATABASE tempdb MODIFY FILE (NAME = tempdev, FILENAME = 'T:tempdb.mdf')
Go
ALTER DATABASE tempdb MODIFY FILE (NAME = templog, FILENAME = 'T:templog.ldf')
Go

backup log HBS_Dongcheng with no_loggodbcc shrinkdatabase (HBS_Dongcheng)go

truncate table TableName

SET IDENTITY_INSERT [ database.[ owner.] ] { table } { ON | OFF }
SET IDENTITY_INSERT products ON

if   exists   (select   *   from   dbo.sysobjects   where   id   =   object_id(N'[dbo].[p_deletefield]')   and   OBJECTPROPERTY(id,   N'IsProcedure')   =   1)   
  drop   procedure   [dbo].[p_deletefield]   
  GO   
    
  /*--删除某字段的所有关系及该字段   
    
  删除某字段时,常常因为在该字段上定义了约束/外键/默认值   
  导致字段删除失败,此存储过就是删除表中指定字段的这些关系   
    
  修正2004.05发布的删除处理中的错误,同时改原来的处理语句为通用存储过程   
    
  --邹建   2004.07(引用请保留此信息)--*/   
    
  /*--调用示例   
    
  exec   p_deletefield   '表名','字段名'   
  --*/   
  create   proc   p_deletefield   
  @tbname   sysname, --要处理的表名   
  @fdname   sysname, --要处理的字段名   
  @delfield   bit=1 --0只删除关系,1同时删除字段   
  as   
  declare   hCForEach   cursor   global   for   
  --默认值约束   
  select   sql='alter   table   ['+b.name+']   drop   constraint   ['+d.name+']'   
  from   syscolumns   a   
  join   sysobjects   b   on   a.id=b.id   and   a.name=@fdname   and   b.name=@tbname     
  join   syscomments   c   on   a.cdefault=c.id   
  join   sysobjects   d   on   c.id=d.id   
  union --外键引用   
  select   s='alter   table   ['+c.name+']   drop   constraint   ['+b.name+']'   
  from   sysforeignkeys   a   
  join   sysobjects   b   on   b.id=a.constid   
  join   sysobjects   c   on   c.id=a.fkeyid   
  join   syscolumns   d   on   d.id=c.id   and   a.fkey=d.colid   and   d.name=@fdname   
  join   sysobjects   e   on   e.id=a.rkeyid   and   e.name=@tbname   
  join   syscolumns   f   on   f.id=e.id   and   a.rkey=f.colid     
  union --主键/唯一键/索引   
  select   case   when   e.xtype   in('PK','UQ')   then   'alter   table   ['+c.name+']   drop   constraint   ['+e.name+']'   
  else   'drop   index   ['+c.name+'].['+a.name+']'   end   
  from   sysindexes   a   
  join   sysindexkeys   b   on   a.id=b.id   and   a.indid=b.indid   
  join   sysobjects   c   on   b.id=c.id   and   c.xtype='U'   and   c.name=@tbname   
  join   syscolumns   d   on   b.id=d.id   and   b.colid=d.colid   and   d.name=@fdname   
  left   join   sysobjects   e   on   e.id=object_id(a.name)   
  where   a.indid   not   in(0,255)   
    
  exec   sp_msforeach_worker   '?'   
    
  if   @delfield=1   
  exec('alter   table   ['+@tbname+']   drop   column   ['+@fdname+']')   
  go