请问这个我的数据库程序有什么问题 [英] Please what is wrong with this my database program
问题描述
如果我使用所声明的连接字符串，以下代码可以工作（除了CREATE TABLE查询），但如果我使用注释掉的连接字符串则无法工作。
通常，无论我是否使用已注释掉的查询，CreateNewDataBase函数都有效。
但一般问题是所有需要密码的连接字符串，最大缓冲区大小或最大数据库大小无法工作，而是抛出异常。
抛出异常的详细信息如下：
描述：生成多步OLE BD操作errors.Check每个OLE DB值（如果可用）。没有工作;
消息：IDispatch错误＃3105
可能是因为我使用的是sql server ce 3的版本， 5附带VS？
除此之外，当我使用不包含密码，最大缓冲区大小和最大数据库大小的连接字符串时，程序运行但是尝试执行CREATE TABLE查询时出现异常。
引发的异常的详细信息是：
描述：（null）;
消息：指针无效。
请问我的CREATE TABLE查询有什么问题？
PS：
我已经搜索了IDispatch错误＃3105，但没有得到满意的信息。
The following code works ( apart from the CREATE TABLE query) if I use the stated connection string, but fails to work if I use the commented out connection strings.
Generally the CreateNewDataBase function works whether I use the commented out query or not.
But the general problem is that all connection strings that require a Password,a Max Buffer Size or Max Database Size fails to work, instead it throws an exception.
The detail of the exception thrown is as follows:
Description:Multiple-Step OLE BD operation generated errors.Check each OLE DB value, if available. No work was done;
Message:IDispatch error #3105
Could it be because I am using the version of sql server ce 3,5 that comes with VS?
Apart from this, when I use the connection string that does not include Password , Max Buffer Size and Max Database size, the program runs but trows an exception while trying to execute the CREATE TABLE query.
The detail of the exception thrown is:
Description:(null);
Message: Invalid pointer.
Please what is wrong with my CREATE TABLE query?
P.S.:
I have googled over the IDispatch error #3105 but have gotten no satisfactory information.
#include "stdafx.h"
#include<Ole2.h>
#include<tchar.h>
#include<strsafe.h>
#import "C:\Program Files\Common Files\System\Ado\msado15.dll" no_namespace rename("EOF","EndOfFile")
int CreateNewDataBase(TCHAR *szConnString,TCHAR *szNewDataSource,TCHAR *szNewPassword)
{
TCHAR szString[1000];
_ConnectionPtr Conn = NULL;
_CommandPtr Cmd = NULL;
try
{
//Create an open connection
Conn.CreateInstance(__uuidof(Connection));
Conn->ConnectionString = _bstr_t(szConnString);
Conn->Open(_bstr_t(L""),_bstr_t(L""),_bstr_t(L""),-1);
//StringCbPrintf(szString,sizeof(szString),_T("CREATE DATABASE \"%s\" DATABASEPASSWORD '%s' COLLATE Latin1_General_CI_AS"),szNewDataSource,szNewPassword);
StringCbPrintf(szString,sizeof(szString),_T("CREATE DATABASE \"%s\""),szNewDataSource);
//Create a new database
Cmd.CreateInstance(__uuidof(Command));
Cmd->ActiveConnection = Conn;
Cmd->CommandText = _bstr_t(szString);
Cmd->Execute(NULL,NULL,adCmdText);
Conn->Close();
}
catch(_com_error &e)
{
_bstr_t Error = e.Description();
TCHAR *szDescription = (TCHAR *)Error;
const TCHAR * szError = e.ErrorMessage();
StringCbPrintf(szString,sizeof(szString),_T("Description : %s ; Message : %s"),szDescription,szError);
//IErrorInfo *IError = e.ErrorInfo();
MessageBox(NULL,szString,_T("Class Creation Error"),MB_OK);
if(Conn)
{
Conn->Close();
}
return 0;
}
return 1;
}
int CreateTables(TCHAR *szConnString,int iTermID,int iTestID)
{
_ConnectionPtr Conn = NULL;
_CommandPtr Cmd = NULL;
TCHAR szString[1000];
try
{
//Create an open connection
Conn.CreateInstance(__uuidof(Connection));
Conn->ConnectionString = _bstr_t(szConnString);
Conn->Open(_bstr_t(L""),_bstr_t(L""),_bstr_t(L""),-1);
//Create SchInfo tableNOT NULL UNIQUE PRIMARY KEY
StringCbPrintf(szString,sizeof(szString),_T("%s %s"),
_T("CREATE TABLE SchInfo (SchInfoID int IDENTITY(1,1) NOT NULL UNIQUE PRIMARY KEY, Name nvarchar(200) NOT NULL,Logo nvarchar(500),Street nvarchar (50) NOT NULL, Locality nvarchar(50) NOT NULL,"),
_T("City nvarchar(50) NOT NULL, State nvarchar(50) NOT NULL, Country nvarchar(50) NOT NULL, EMail nvarchar(50) UNIQUE, Phone nvarchar(20) UNIQUE);"));
Cmd->CommandText = _bstr_t(szString);
Cmd->Execute(NULL,NULL,adCmdText);
Conn->Close();
}
catch(_com_error &e)
{
_bstr_t Error = e.Description();
TCHAR *szDescription = (TCHAR *)Error;
const TCHAR * szError = e.ErrorMessage();
StringCbPrintf(szString,sizeof(szString),_T("Description : %s ; Message : %s"),szDescription,szError);
//IErrorInfo *IError = e.ErrorInfo();
MessageBox(NULL,szString,_T("Class Creation Error"),MB_OK);
if(Conn)
{
Conn->Close();
}
return 0;
}
return 1;
}
int main()
{
::CoInitializeEx(NULL,COINIT_MULTITHREADED);
TCHAR szNewDataSource[] = _T("Test.sdf");
TCHAR szNewPassword[] = _T("Password");
TCHAR szOldDataSource[] = _T("C:\\Users\\user\\Documents\\MyDataBase.sdf");
int iTermID = 1, iTestID = 1;
// Password = '%s'; File Mode = 'shared read'; Max Database Size = '256'; Max Buffer Size = '256'
TCHAR szOldPassword[] = _T("OldPassword");
TCHAR szConnString[1000];
//StringCbPrintf(szConnString,sizeof(szConnString),_T("Provider='Microsoft.SQLSERVER.CE.OLEDB.3.5';Persist Security Info='FALSE';Data Source='%s';Password = '%s'; File Mode = 'shared read'; Max Database Size = '256'; Max Buffer Size = '256"),szOldDataSource,szOldPassword);
StringCbPrintf(szConnString,sizeof(szConnString),_T("Provider='Microsoft.SQLSERVER.CE.OLEDB.3.5';Persist Security Info='FALSE';Data Source='%s';"),szOldDataSource);
if(CreateNewDataBase(szConnString,szNewDataSource,szNewPassword))
{
//StringCbPrintf(szConnString,sizeof(szConnString),_T("Provider = 'Microsoft.SQLSERVER.CE.OLEDB.3.5'; Persist Security Info = 'FALSE'; Data Source = '%s'; Password = '%s'; File Mode = 'shared read'; Max Database Size = '4000'; Max Buffer Size = '1024'; "),szNewDataSource,szNewPassword);
StringCbPrintf(szConnString,sizeof(szConnString),_T("Provider = 'Microsoft.SQLSERVER.CE.OLEDB.3.5'; Persist Security Info = 'FALSE'; Data Source = '%s';"),szNewDataSource);
if(CreateTables(szConnString,iTermID,iTestID))
{
MessageBox(NULL,_T("New database and table were successfully created."),_T("Database Creation Success"),MB_OK);
}
}
else
{
MessageBox(NULL,_T("Could not create database and table."),_T("Database Creation Failure"),MB_OK);
}
::CoUninitialize();
return 1;
}
推荐答案
这与您之前的问题基本相同：请问这个我的c ++新数据库创建代码出了什么问题？ [ ^ ]。
然而在声明中：
This is essentially the same as your previous question: Please what is wrong with this my c++ new database creation code?[^].
However in the statement:
Cmd->Execute(NULL,NULL,adCmdText);
在哪里宣布 adCmdText 它应该是什么？
我注意到你也没有检查所有COM调用的结果代码，如上一个问题所示。为初始测试尝试更简单的数据库结构可能是个好主意，然后添加额外的参数和选项直到出现故障，看看哪个项目导致问题。
where is adCmdText declared and what is it supposed to be?
I notice that you are also not checking the result codes from all the COM calls, as suggested in the previous question. It would probably be a good idea to try a much simpler database structure for your initial testing, and then add extra parameters and options until you get failures, to see which item is causing the problem.
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