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怎样用代码压缩access数据库?解决思路

发布时间: 2012-09-10 11:02:32 作者: rapoo

怎样用代码压缩access数据库?
由于access数据库写多了会很大,虽然里面的纪录少,但是空间却大的惊人,用access本身的功能一压缩,便可节省大量空间,可是找到许多代码都不能用啊,谁有啊,给个啊。假设我的文件路径为 D:\A.mdb,只把数据库密码设置为123,怎样压缩?

[解决办法]
uses ComObj;
function DaoActive(var DaoObject: OleVariant): Boolean;
begin
Result:=False;
try
DaoObject:=GetActiveOleObject('DAO.DBEngine.36');
Result:=True;
except
try
DaoObject:=CreateOleObject('DAO.DBEngine.36');
Result:=True;
except
DaoObject:=Null;
end;
end;
end;
//压缩数据库
var
db:OleVariant;
TempFile:string;
FilePath:string;
begin
try
if not DaoActive(db) then
Exit;
try
TempFile:='D:\tempA.mdb';//临时文件
db.CompactDatabase('D:\A.mdb',TempFile,';PWD=123',0,';PWD=123');
DeleteFile(PChar('D:\A.mdb'));//删除原文件
RenameFile(TempFile,'D:\A.mdb');//重命名
except
on E:EOleException do
ShowMessage(E.Message);
end
finally
db:=Unassigned;
end;
[解决办法]

探讨
uses ComObj;
function DaoActive(var DaoObject: OleVariant): Boolean;
begin
Result:=False;
try
DaoObject:=GetActiveOleObject('DAO.DBEngine.36');
Result:=True;
except
try
DaoObject:=CreateOleObject('DAO.DBEngine.36');
Result:=True;
except
DaoObject:=Null;
end;
end;
end;
//压缩数据库
var
db:Ol…

[解决办法]
以下是本人在Delphi 10+Windows Server 2003中的成功应用,屡试不爽:
Delphi(Pascal) code
//压缩数据库并制作新密码数据库副本 for Access//需引用的单元: ComObj, VariantsprocedureDBCompress;var  vJE:OleVariant;begin  try    try      vJE:=CreateOleObject('JRO.JetEngine');      vJE.CompactDatabase(Format(sConn,[JobPath + 'DATA.mdb','OldPassword']),        Format(sConn,[JobPath + 'DATA.mdbx','OldPassword']));      DeleteFile(PChar(JobPath + 'DATA.mdb'));      RenameFile(JobPath + 'DATA.mdbx',JobPath + 'DATA.mdb');      //更改数据库密码 2008-03-05      //vJE.CompactDatabase(format(SConnectionString,[GetTempDir + 'DATA.mdb','OldPassword']),      //  format(SConnectionString,[GetTempDir + 'NewDATA.mdb','NewPassword']));    finally      vJE:= Unassigned;    end;  except    vJE:= Unassigned;  end;end;
[解决办法]
压缩或更改密码的前提是:
将所有与该数据库的链接全部断开.因为这种操作需要独占方式.
[解决办法]
将数据库压缩并设置密码:

uses comobj;

procedure TForm1.Button1Click(Sender: TObject);
var
dbe:OleVariant;
begin
dbe:=CreateOleObject('dao.dbengine.36');
dbe.CompactDatabase('D:\a.mdb','d:\b.mdb','',0,';pwd=mima');
end;
[解决办法]
以下代码在Delphi6+Office2000正常用过
Delphi(Pascal) code
//引用ComObj,ActiveXfunction TFAutoStat.CompactDatabase(AFileName,APassWord:string):boolean;//压缩与修复数据库,覆盖源文件const  SConnectionString = 'Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s;'      +'Jet OLEDB:Database Password=%s;';var  SPath,SFile:Array [0..254] Of Char;  STempFileName:String;  JE:OleVariant;begin  GetTempPath(40,SPath);//取得Windows的Temp路径  GetTempFileName(SPath,'~CP',0,SFile);//取得Temp文件名,Windows将自动建立0字节文件  STempFileName:=SFile;//PChar->String  DeleteFile(STempFileName);//删除Windows建立的0字节文件  try    JE:=CreateOleObject('JRO.JetEngine');//建立OLE对象,函数结束OLE对象超过作用域自动释放    OleCheck(JE.CompactDatabase(format(SConnectionString,[AFileName,APassWord]),        format(SConnectionString,[STempFileName,APassWord])));//压缩数据库    //复制并覆盖源数据库文件,如果复制失败则函数返回假,压缩成功但没有达到函数的功能    result:=CopyFile(PChar(STempFileName),PChar(AFileName),false);    DeleteFile(STempFileName);//删除临时文件  except    result:=false;//压缩失败  end;end;procedure TFAutoStat.ActCompactDBExecute(Sender: TObject);var  sFileName: String;begin  sFileName:=ExtractFilePath(Application.ExeName)+'..\DataBase\AutoStat.mdb';  sBarText('正在压缩数据库,请稍候......');  Self.Enabled:=false;  Self.Cursor:=crSqlWait;  try    AdoConnection.Close; //需要断开数据库    if  CompactDatabase(sFileName,'1234') then sBarText('压缩数据库完毕')      else ShowMessage('压缩数据库失败!');    ConnectToDB();  finally    Self.Enabled:=true;    Self.Cursor:=crDefault;  end;end; 

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