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获得当前数据库对象依赖关系的实用算法
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本文主要介绍了一个获得当前数据库对象依赖关系的实用算法，具体示例请大家参考下文：
以下为引用的内容：
create function udf_GenLevelPath()
returns @v_Result table (LevelPath int,OName sysname)
/****************************************************************/
/* 功能描述：按照依赖关系，列出数据库对象 */
/* 输入参数：无 */
/* 输出参数：按照依赖关系排列的数据库对象表，无依赖在前 */
/* 编写： anna*/
/* 时间：2007-12-12 */
/****************************************************************/
as
begin
declare @vt_ObjDepPath table (LevelPath int,OName sysname null)
declare @vt_Temp1 table (OName sysname null)
declare @vt_Temp2 table (OName sysname null)
--依赖的级别，值越小依赖性越强
declare @vi_LevelPath int
set @vi_LevelPath = 1
--得到所有对象，不包括系统对象
insert into @vt_ObjDepPath(LevelPath,OName)
select @vi_LevelPath,o.name
from sysobjects o
where xtype not in ('S','X')
--得到依赖对象的名称
insert into @vt_Temp1(OName)
select distinct object_name(sysdepends.depid)
from sysdepends,@vt_ObjDepPath p
where sysdepends.id <> sysdepends.depid
and p.OName = object_name(sysdepends.id)
--循环处理：由对象而得到其依赖对象
while (select count(*) from @vt_Temp1) > 0
begin
set @vi_LevelPath = @vi_LevelPath + 1
update @vt_ObjDepPath
set LevelPath = @vi_LevelPath
where OName in (select OName from @vt_Temp1)
and LevelPath = @vi_LevelPath - 1
delete from @vt_Temp2
insert into @vt_Temp2
select * from @vt_Temp1
delete from @vt_Temp1
insert into @vt_Temp1(OName)
select distinct object_name(sysdepends.depid)
from sysdepends,@vt_Temp2 t2
where t2.OName = object_name(sysdepends.id)
and sysdepends.id <> sysdepends.depid
end
select @vi_LevelPath = max(LevelPath) from @vt_ObjDepPath
--修改没有依赖对象的对象级别为最大
update @vt_ObjDepPath
set LevelPath = @vi_LevelPath + 1
where OName not in (select distinct
object_name(sysdepends.id) from sysdepends)
and LevelPath = 1
insert into @v_Result
select * from @vt_ObjDepPath order by LevelPath desc
return
end
go
--调用方法
select * from dbo.udf_GenLevelPath()
go
以下为引用的内容：
create function udf_GenLevelPath()
returns @v_Result table (LevelPath int,OName sysname)
/****************************************************************/
/* 功能描述：按照依赖关系，列出数据库对象 */
/* 输入参数：无 */
/* 输出参数：按照依赖关系排列的数据库对象表，无依赖在前 */
/* 编写： anna*/
/* 时间：2007-12-12 */
/****************************************************************/
as
begin
declare @vt_ObjDepPath table (LevelPath int,OName sysname null)
declare @vt_Temp1 table (OName sysname null)
declare @vt_Temp2 table (OName sysname null)
--依赖的级别，值越小依赖性越强
declare @vi_LevelPath int
set @vi_LevelPath = 1
--得到所有对象，不包括系统对象
insert into @vt_ObjDepPath(LevelPath,OName)
select @vi_LevelPath,o.name
from sysobjects o
where xtype not in ('S','X')
--得到依赖对象的名称
insert into @vt_Temp1(OName)
select distinct object_name(sysdepends.depid)
from sysdepends,@vt_ObjDepPath p
where sysdepends.id <> sysdepends.depid
and p.OName = object_name(sysdepends.id)
--循环处理：由对象而得到其依赖对象
while (select count(*) from @vt_Temp1) > 0
begin
set @vi_LevelPath = @vi_LevelPath + 1
update @vt_ObjDepPath
set LevelPath = @vi_LevelPath
where OName in (select OName from @vt_Temp1)
and LevelPath = @vi_LevelPath - 1
delete from @vt_Temp2
insert into @vt_Temp2
select * from @vt_Temp1
delete from @vt_Temp1
insert into @vt_Temp1(OName)
select distinct object_name(sysdepends.depid)
from sysdepends,@vt_Temp2 t2
where t2.OName = object_name(sysdepends.id)
and sysdepends.id <> sysdepends.depid
end
select @vi_LevelPath = max(LevelPath) from @vt_ObjDepPath
--修改没有依赖对象的对象级别为最大
update @vt_ObjDepPath
set LevelPath = @vi_LevelPath + 1
where OName not in (select distinct
object_name(sysdepends.id) from sysdepends)
and LevelPath = 1
insert into @v_Result
select * from @vt_ObjDepPath order by LevelPath desc
return
end
go
--调用方法
select * from dbo.udf_GenLevelPath()
go