Access数据库在线压缩的实现: 如果在 Access 数据库中删除数据或对象,或者在 Access 项目中删除对象,Access 数据库或 Access 项目可能会产生碎片并会降低磁盘空间的使用效率。压缩 Access 数据库或Access项目实际上是复制该文件,并重新组织文件在磁盘上
Access数据库在线压缩的实现:
如果在 Access 数据库中删除数据或对象,或者在 Access 项目中删除对象,Access 数据库或 Access 项目可能会产生碎片并会降低磁盘空间的使用效率。压缩 Access 数据库或Access项目实际上是复制该文件,并重新组织文件在磁盘上的存储方式。压缩同时优化了 Access 数据库和 Access 项目的性能。
所以我们在对日益增大的数据库导致的ASP程序慢得无法忍受的时候,就想到了要压缩他。但常规的做法把他下载到本地然后用MSaccess来完成压缩操作,然后再上传!后来我想是否可以在线实现对ACCESS数据库的压缩呢?为此我查了一些资料,但还是不得要领。
我在本机测试获得成功,又上网对自己的动网论坛实施了压缩操作结果也完全正常,数据库从原来的3.7M压缩到了2.1M从而证实是可行的。需要注意的是:本程序其实是通过FSO权限和JET引擎连接,因此在使用之前请确认你的服务器支持FSO(filesystemobject)权限并安装的ACCESS最新驱动!从安全出发,请在压缩之前备份原始数据库!已经测试通过的运行环境:
WIN98SE+PWS、WIN2000+IIS5.0
下面是我整理后的源代码,复制另存为compact.asp并上传到数据库所在目录即可正常使用。
本程序其实是通过FSO权限和JET引擎连接,因此在使用之前请确认你的服务器支持FSO(filesystemobject)权限并安装的ACCESS最新驱动!从安全出发,请在压缩之前备份原始数据库!
Const JET_3X = 4
Function CompactDB(dbPath, boolIs97)
Dim fso, Engine, strDBPath
strDBPath = left(dbPath,instrrev(DBPath,""))
Set fso = CreateObject("Scripting.FileSystemObject")
If fso.FileExists(dbPath) Then
Set Engine = CreateObject("JRO.JetEngine")
If boolIs97 = "True" Then
Engine.CompactDatabase "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & dbpath, _
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & strDBPath & "temp.mdb;" _
& "Jet OLEDB:Engine Type=" & JET_3X
Else
Engine.CompactDatabase "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & dbpath, _
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & strDBPath & "temp.mdb"
End If
fso.CopyFile strDBPath & "temp.mdb",dbpath
fso.DeleteFile(strDBPath & "temp.mdb")
Set fso = nothing
Set Engine = nothing
CompactDB = "你的数据库, " & dbpath & ", 已经被压缩" & vbCrLf
Else
CompactDB = "你输入的数据库路径或名称未找到,请重试" & vbCrLf
End If
End Function
%>
Dim dbpath,boolIs97
dbpath = request("dbpath")
boolIs97 = request("boolIs97")
If dbpath "" Then
dbpath = server.mappath(dbpath)
response.write(CompactDB(dbpath,boolIs97))
End If
%>

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