SQLServer数据库从高版本降级到低版本实例有哪些？

SET QUOTED_IDENTIFIER ON 
 SET ANSI_NULLS ON 
 GO 
 create procedure sys.sp_dbcmptlevel   -- 1997/04/15 
 @dbname sysname = NULL,     -- database name to change 
 @new_cmptlevel tinyint = NULL OUTPUT -- the new compatibility level to change to 
 as 
 set nocount on 
 
 declare @exec_stmt nvarchar(max) 
 declare @returncode int 
 declare @comptlevel float(8) 
 declare @dbid int     -- dbid of the database 
 declare @dbsid varbinary(85)  -- id of the owner of the database 
 declare @orig_cmptlevel tinyint  -- original compatibility level 
 declare @input_cmptlevel tinyint -- compatibility level passed in by user 
  ,@cmptlvl80 tinyint    -- compatibility to SQL Server Version 8.0 
  ,@cmptlvl90 tinyint    -- compatibility to SQL Server Version 9.0 
  ,@cmptlvl100 tinyint    -- compatibility to SQL Server Version 10.0 
 select @cmptlvl80 = 80, 
   @cmptlvl90 = 90, 
   @cmptlvl100 = 100 
 
 -- SP MUST BE CALLED AT ADHOC LEVEL -- 
 if (@@nestlevel > 1) 
 begin 
  raiserror(15432,-1,-1,'sys.sp_dbcmptlevel') 
  return (1) 
 end 
 
 -- If no @dbname given, just list the valid compatibility level values. 
 if @dbname is null 
 begin 
  raiserror (15048, -1, -1, @cmptlvl80, @cmptlvl90, @cmptlvl100) 
  return (0) 
 end 
 
 -- Verify the database name and get info 
 select @dbid = dbid, @dbsid = sid ,@orig_cmptlevel = cmptlevel 
  from master.dbo.sysdatabases 
  where name = @dbname 
 
 -- If @dbname not found, say so and list the databases. 
 if @dbid is null 
 begin 
  raiserror(15010,-1,-1,@dbname) 
  print ' ' 
  select name as 'Available databases:' 
   from master.dbo.sysdatabases 
  return (1) 
 end 
 
 -- Now save the input compatibility level and initialize the return clevel 
 -- to be the current clevel 
 select @input_cmptlevel = @new_cmptlevel 
 select @new_cmptlevel = @orig_cmptlevel 
 
 -- If no clevel was supplied, display and output current level. 
 if @input_cmptlevel is null 
 begin 
  raiserror(15054, -1, -1, @orig_cmptlevel) 
  return(0) 
 end 
 
 -- If invalid clevel given, print usage and return error code 
 -- 'usage: sp_dbcmptlevel [dbname [, compatibilitylevel]]' 
 if @input_cmptlevel not in (@cmptlvl80, @cmptlvl90, @cmptlvl100) 
 begin 
  raiserror(15416, -1, -1) 
  print ' ' 
  raiserror (15048, -1, -1, @cmptlvl80, @cmptlvl90, @cmptlvl100) 
  return (1) 
 end 
 
 -- Only the SA or the dbo of @dbname can execute the update part 
 -- of this procedure sys.so check. 
 if (not (is_srvrolemember('sysadmin') = 1)) and suser_sid() <> @dbsid 
  -- ALSO ALLOW db_owner ONLY IF DB REQUESTED IS CURRENT DB 
  and (@dbid <> db_id() or is_member('db_owner') <> 1) 
 begin 
  raiserror(15418,-1,-1) 
  return (1) 
 end 
 
 -- If we're in a transaction, disallow this since it might make recovery impossible. 
 set implicit_transactions off 
 if @@trancount > 0 
 begin 
  raiserror(15002,-1,-1,'sys.sp_dbcmptlevel') 
  return (1) 
 end 
 
 set @exec_stmt = 'ALTER DATABASE ' + quotename(@dbname, '[') + ' SET COMPATIBILITY_LEVEL = ' + cast(@input_cmptlevel as nvarchar(128)) 
 
 -- Note: database @dbname may not exist anymore 
 exec(@exec_stmt) 
 
 select @new_cmptlevel = @input_cmptlevel 
 
 return (0) -- sp_dbcmptlevel 
 GO 

sp_dbcmptlevel [ [ @dbname = ] name ] [ , [ @new_cmptlevel = ] version ] 

[ @dbname = ] name