【IT168技术文档】

　　扩展sp_MSforeach(一)

　　本文浅析SQL SERVER一个没有公开的存储过程中介绍了sp_MSforeachtable的工作方式和工作原理。不过令人失望的是它们不能扩展到其它的对象（比如视图、存储过程、触发器等）。那我们就自己对手来完全扩展这些存储过程。

　　sp_MSforeachsproc 存储过程：

USE MASTER
GO
if exists (select name from sysobjects
where name = 'sp_MSforeachsproc' AND type = 'P')
drop procedure sp_MSforeachsproc
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO
create proc sp_MSforeachsproc
@command1 nvarchar(2000), @replacechar nchar(1) = N'?', @command2 nvarchar(2000) = null,
@command3 nvarchar(2000) = null, @whereand nvarchar(2000) = null,
@precommand nvarchar(2000) = null, @postcommand nvarchar(2000) = null
as
/**//* This proc returns one or more rows for each table (optionally, matching @where), 
with each table defaulting to its own result set */
/**//* @precommand and @postcommand may be used to force a single result set via a temp table. */
/**//* Preprocessor won't replace within quotes so have to use str(). */
declare @mscat nvarchar(12)
select @mscat = ltrim(str(convert(int, 0x0002)))
if (@precommand is not null)
exec(@precommand)
/**//* Create the select */
exec(N'declare hCForEach cursor global for select ''['' 
         + REPLACE(user_name(uid), N'']'', N'']]'') 
         + '']'' + ''.'' + ''['' + REPLACE(object_name(id), N'']'', N'']]'') + '']'' 
          from dbo.sysobjects o '
+ N' where OBJECTPROPERTY(o.id, N''IsProcedure'') = 1 ' + N' 
          and o.category & ' + @mscat + N' = 0 '
+ @whereand)
declare @retval int
select @retval = @@error
if (@retval = 0)
exec @retval = sp_MSforeach_worker @command1, @replacechar, @command2, @command3
if (@retval = 0 and @postcommand is not null)
exec(@postcommand)
return @retval
GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO

　　sp_MSforeachtrigger 触发器：

USE MASTER
GO
if exists (select name from sysobjects
where name = 'sp_MSforeachtrigger' AND type = 'P')
drop procedure sp_MSforeachtrigger
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO
create proc sp_MSforeachtrigger
@command1 nvarchar(2000), @replacechar nchar(1) = N'?', @command2 nvarchar(2000) = null,
@command3 nvarchar(2000) = null, @whereand nvarchar(2000) = null,
@precommand nvarchar(2000) = null, @postcommand nvarchar(2000) = null
as
/**//* This proc returns one or more rows for each table (optionally, matching @where), 
        with each table defaulting to its own result set */
/* @precommand and @postcommand may be used to 
force a single result set via a temp table. */
/**//* Preprocessor won't replace within quotes so have to use str(). */
declare @mscat nvarchar(12)
select @mscat = ltrim(str(convert(int, 0x0002)))
if (@precommand is not null)
exec(@precommand)
/**//* Create the select */
exec(N'declare hCForEach cursor global for select ''['' 
         + REPLACE(user_name(uid), N'']'', N'']]'')  
         + '']'' + ''.''+ ''['' + REPLACE(object_name(id), N'']'', N'']]'') + '']'' 
         from dbo.sysobjects o '
+ N' where OBJECTPROPERTY(o.id, N''IsTrigger'') = 1 ' + N' 
         and o.category & ' + @mscat + N' = 0 '
+ @whereand)
declare @retval int
select @retval = @@error
if (@retval = 0)
exec @retval = sp_MSforeach_worker @command1, @replacechar, @command2, @command3
if (@retval = 0 and @postcommand is not null)
exec(@postcommand)
return @retval
GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO