请问如何用程序控制压缩Access2000数据库？
就是相当于执行access菜单栏里的“修复和压缩数据库”的功能 问题点数：20、回复次数：12Top
1 楼jiangsheng（蒋晟.Net[MVP]）回复于 2002-01-17 11:06:57 得分 0
CDaoWorkspace::CompactDatabase
static void PASCAL CompactDatabase( LPCTSTR lpszSrcName, LPCTSTR lpszDestName, LPCTSTR lpszLocale = dbLangGeneral, int nOptions = 0 );
throw( CDaoException, CMemoryException );
static void PASCAL CompactDatabase( LPCTSTR lpszSrcName, LPCTSTR lpszDestName, LPCTSTR lpszLocale, int nOptions, LPCTSTR lpszPassword );
throw( CDaoException, CMemoryException );
Parameters
lpszSrcName
The name of an existing, closed database. It can be a full path and filename, such as “C:\\MYDB.MDB”. If the filename has an extension, you must specify it. If your network supports the uniform naming convention (UNC), you can also specify a network path, such as “\\\\MYSERVER\\MYSHARE\\MYDIR\\MYDB.MDB”. (Double backslashes are required in the path strings because “\” is the C++ escape character.)
lpszDestName
The full path of the compacted database that you are creating. You can also specify a network path as with lpszSrcName. You cannot use the lpszDestName argument to specify the same database file as lpszSrcName.
lpszPassword
A password, used when you want to compact a password-protected database. Note that if you use the version of CompactDatabase that takes a password, you must supply all parameters. Also, because this is a connect parameter, it requires special formatting, as follows: ;PWD=lpszPassword. For example: ;PWD=“Happy”. (The leading semicolon is required.)
lpszLocale
A string expression used to specify collating order for creating lpszDestName. If you omit this argument by accepting the default value of dbLangGeneral (see below), the locale of the new database is the same as that of the old database. Possible values are:
dbLangGeneral English, German, French, Portuguese, Italian, and Modern Spanish
dbLangArabic Arabic
dbLangCyrillic Russian
dbLangCzech Czech
dbLangDutch Dutch
dbLangGreek Greek
dbLangHebrew Hebrew
dbLangHungarian Hungarian
dbLangIcelandic Icelandic
dbLangNordic Nordic languages (Microsoft Jet database engine version 1.0 only)
dbLangNorwdan Norwegian and Danish
dbLangPolish Polish
dbLangSpanish Traditional Spanish
dbLangSwedfin Swedish and Finnish
dbLangTurkish Turkish
nOptions
Indicates one or more options for the target database, lpszDestName. If you omit this argument by accepting the default value, the lpszDestName will have the same encryption and the same version as lpszSrcName. You can combine the dbEncrypt or dbDecrypt option with one of the version options using the bitwise-OR operator. Possible values, which specify a database format, not a database engine version, are:
dbEncrypt Encrypt the database while compacting.
dbDecrypt Decrypt the database while compacting.
dbVersion10 Create a database that uses the Microsoft Jet database engine version 1.0 while compacting.
dbVersion11 Create a database that uses the Microsoft Jet database engine version 1.1 while compacting.
dbVersion20 Create a database that uses the Microsoft Jet database engine version 2.0 while compacting.
dbVersion30 Create a database that uses the Microsoft Jet database engine version 3.0 while compacting.
You can use dbEncrypt or dbDecrypt in the options argument to specify whether to encrypt or to decrypt the database as it is compacted. If you omit an encryption constant or if you include both dbDecrypt and dbEncrypt, lpszDestName will have the same encryption as lpszSrcName. You can use one of the version constants in the options argument to specify the version of the data format for the compacted database. This constant affects only the version of the data format of lpszDestName. You can specify only one version constant. If you omit a version constant, lpszDestName will have the same version as lpszSrcName. You can compact lpszDestName only to a version that is the same or later than that of lpszSrcName.
CAUTION If a database is not encrypted, it is possible, even if you implement user/password security, to directly read the binary disk file that constitutes the database.
Remarks
Call this member function to compact a specified Microsoft Jet (.MDB) database. As you change data in a database, the database file can become fragmented and use more disk space than necessary. Periodically, you should compact your database to defragment the database file. The compacted database is usually smaller. You can also choose to change the collating order, the encryption, or the version of the data format while you copy and compact the database.
! WARNING The CompactDatabase member function will not correctly convert a complete Microsoft Access database from one version to another. Only the data format is converted. Microsoft Access-defined objects, such as forms and reports, are not converted. However, the data is correctly converted.
Tip You can also use CompactDatabase to copy a database file.
For more information about workspaces, see the articleDAO Workspace in Visual C++ Programmer's Guide. For more information about compacting databases, see the topic "CompactDatabase Method" in DAO Help.
CDaoWorkspace Overview | Class Members | Hierarchy Chart
See Also CDaoWorkspace::RepairDatabase
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2 楼Xsean（）回复于 2002-01-17 11:19:02 得分 0
蒋晟:我没用DAO，我用的ADO,jet4.0引擎，不能用DAO的函数吧Top
3 楼jiangsheng（蒋晟.Net[MVP]）回复于 2002-01-17 11:23:34 得分 0
jet4.0里面用修复数据库那个函数就可以了Top
4 楼Xsean（）回复于 2002-01-17 13:06:32 得分 0
老蒋，找不到这个函数！不是俺不努力，只是......Top
5 楼jiangsheng（蒋晟.Net[MVP]）回复于 2002-01-17 13:38:22 得分 0
……
没有repair开头的？Top
6 楼Xsean（）回复于 2002-01-17 15:02:34 得分 0
只有几个数学、日期之类的函数。以下是我在其他论坛找的一篇贴子，是VB的解决方法,可我在VC下找不到这个东东.:
VB的ADO不能提供这种功能,但可以使用vb提供的Microsoft Jet and Replication来压缩数据库
在引用中选中Microsoft Jet and Replication,然后应用如下代码
Dim j As New JRO.JetEngine
j.CompactDatabase "provider=Microsoft.Jet.OLEDB.4.0;data source=e:\old.mdb", "provider=Microsoft.Jet.OLEDB.4.0;data source=e:\new.mdb;jet oledb:encrypt database=true"
然后删除old.mdb,重命名new.mdb为old.mdb即可 .Top
7 楼Xsean（）回复于 2002-01-17 15:27:00 得分 0
jiangsheng(蒋晟) 快来呀Top
8 楼jiangsheng（蒋晟.Net[MVP]）回复于 2002-01-17 15:40:10 得分 20
#import "C:\PROGRAM FILES\COMMON FILES\System\ado\MSJRO.DLL" no_namespace
Add the following (specifying your own source and destination database paths) to the .cpp file where you want to compact the database:
...
try
{
IJetEnginePtr jet(__uuidof(JetEngine));
jet->CompactDatabase("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\nwind2.mdb", "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\abbc.mdb;Jet OLEDB:Engine Type=4");
}
catch(_com_error &e)
{
::MessageBox(NULL, (LPCTSTR)e.Description( ), "", MB_OK) ;
}
NOTE: The Jet OLEDB:Engine Type=4 is only for Jet 3.x format MDB files. If this value is left out, the database is automatically upgraded to the 4.0 version (Jet OLEDB:Engine Type=5). See the following table for appropriate values for Jet OLEDB:Engine Type:
Jet OLEDB:Engine Type Jet x.x Format MDB Files
1 JET10
2 JET11
3 JET2X
4 JET3X
5 JET4X
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9 楼Xsean（）回复于 2002-01-17 16:57:49 得分 0
老蒋，我服你了，真高手也！我在MSDN上怎么找不到呢？是不是2CD的没有这些内容啊？
另外还有个问题请教，我原来只加了msado15.dll，没有用MSJRO.DLL，可是打开数据时用MyDB->Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=my.mdb","","",adModeUnknown);也没问题啊，那么这个jet 4.0引擎是哪里提供的呢?
还有MSJRO.DLL是随access还是随windows发布的？我如果要打包安装到win98下运行要不要把这些dll一起打包?
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10 楼Xsean（）回复于 2002-01-17 19:51:19 得分 0
upupTop
11 楼jiangsheng（蒋晟.Net[MVP]）回复于 2002-01-17 20:05:52 得分 0
www.microsoft.com/dataTop
12 楼snake1122（surfer）回复于 2002-01-18 10:48:09 得分 0
来看高手！Top
