关于打开Recordset记录集的有关问题

关于打开Recordset记录集的问题
m_pRecordset->Open(_variant_t("select * from 系别信息"),m_pConnection.GetInterfacePtr(),
adOpenStatic,adLockOptimistic,-1);

运行之后为什么会出现DEBUG ERROR R6010

------解决方案--------------------
调式看以下m_pConnection,m_pRecordset是不是为空
------解决方案--------------------
我用的是Xproer.OleDb这个类库，以.Net风格封装的，写起代码来像堆积木一样简单。
下面是使用Xproer.OleDb对数据库进行操作的示例：

C/C++ code


#include "stdafx.h"
#include "XproerDataDef.h"
#include "OleDb/OleDbCommand.h"
#include "OleDb/OleDbConnection.h"
#include "OleDb/OleDbDataReader.h"
#include "OleDb/DataTable.h"
#include "OleDb/DataRow.h"
#include "OleDb/DataValue.h"

using namespace Xproer::OleDb;

//获取DataTable的示例
void ADODataTable(OleDbCommand& cmd)
{
    int count = 0;
    cmd.ExecuteScalar(L"select count(*) from xdb_news",count);
    auto_ptr<DataTable> table;
    table.reset(cmd.ExecuteDataTable(L"select top 10 IsTop from xdb_news"));

    size_t rowCount = table->GetRowsCount();
    for (int i = 0 ; i < rowCount ; ++i)
    {
        DataRow* row = table->GetRow(i);
        DataValue* val = row->GetCel(0);
        
        printf("时间：%d \r\n", val->ToBoolean() );
    }
}

//使用OleDbDataReader快速读取数据的示例
void ADORead(OleDbCommand& cmd)
{
    OleDbDataReader* r = cmd.ExecuteReader(L"select ProductPrice from xdb_news");
    USES_CONVERSION;
    wstring title;
    while(r->Read())
    {
        //r->GetString(0,title);        
        //printf("标题：%s \r\n",W2A(title.c_str()));
        printf("ID：%f \r\n", r->GetFloat(0) );
    }
    r->Close();
}

//通过变量向数据库安全添加数据的示例
void ADOAdd(OleDbCommand& cmd)
{
    cmd.SetCommandText(L"insert into xdb_about(VDouble) values(@VDouble)");
    cmd.AddDoubleParam(L"@VDouble",125022.3180);

    cmd.ExecuteNonQuery();
}

//高性能向数据库插入数据的示例
void ADOParam(OleDbCommand& cmd)
{
    cmd.SetCommandText(L"delete from xdb_news where ID=@ID;");
    cmd.AddInt32Param(L"@ID",886);
    cmd.SetPrepared(true);

    _variant_t index = (short)0;
    _ParameterPtr param = cmd.GetCommand()->Parameters->GetItem(index);
    param->Value = 887;
    cmd.ExecuteNonQuery();
    param->Value = 888;
    cmd.ExecuteNonQuery();
    param->Value = 889;
    cmd.ExecuteNonQuery();
    param->Value = 890;
    cmd.ExecuteNonQuery();
    param->Value = 891;
    cmd.ExecuteNonQuery();
}

//向数据库添加实数的示例
void NumericScaleX(OleDbCommand& cmd)
{
    OleDbDataReader* r = cmd.ExecuteReader(L"select ProductPrice from xdb_news");
    _RecordsetPtr& rs = r->GetRecordsetPtr();
    rs->MoveFirst();

    _variant_t vi = (short)0;
    FieldPtr fd = rs->Fields->GetItem(vi);
    unsigned char numeri = fd->GetNumericScale();
    unsigned char precision = fd->GetPrecision();

    printf("GetNumericScale:%d\r\n", fd->GetNumericScale() );
    printf("GetPrecision:%d\r\n", fd->GetPrecision() );
    printf("Value:%f\r\n", (float)fd->Value );
    r->Close();
}

int _tmain(int argc, _TCHAR* argv[])
{
    ::CoInitialize(NULL);
    OleDbConnection con;
    con.SetAccessConStr(L"F:\\vc9\\adoDemo\\Debug\\db.mdb");
    con.Open();

    OleDbCommand cmd(&con);

    ADORead(cmd);
    
    con.Close();

    ::CoUninitialize();
    //printf("总数：%d",count);
    system("pause");
    return 0;
}

------解决方案--------------------

m_pRecordset初始化了吗？

关于打开Recordset记录集的有关问题

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