Question

我有一张这样的表：

__fastcall UploadRouteThread::UploadRouteThread(String host, TIdPort port, AnsiString xmlString)
    : TThread(false)
{
    this->FreeOnTerminate = true;
    this->OnTerminate = OnTerminateHandler;
    this->xmlString = xmlString;

    tcpClient = new TIdTCPClient();
    tcpClient->Host = host;
    tcpClient->Port = port;
    tcpClient->UseNagle = true;
    tcpClient->OnWork = OnWorkHandler;
}

__fastcall UploadRouteThread::~UploadRouteThread()
{
    delete tcpClient;
}

void __fastcall UploadRouteThread::OnTerminateHandler(TObject *Sender)
{
    TabbedwithNavigationForm->UploadButton->Text = "Upload";
    TabbedwithNavigationForm->UploadButton->Enabled = false;
    TabbedwithNavigationForm->ProgressBar->Visible = false;

    if (FatalException)
        ShowMessage("Data not uploaded.");
    else
        ShowMessage("Data uploaded.");

    TabbedwithNavigationForm->OptionButton->Enabled = true;
    TabbedwithNavigationForm->RetrieveRoutesButton->Enabled = true;
    TabbedwithNavigationForm->TrackButton->Enabled = true;
    TabbedwithNavigationForm->MediaButton->Enabled = true;
}

void __fastcall UploadRouteThread::OnWorkHandler(TObject *ASender, TWorkMode AWorkMode, __int64 AWorkCount)
{
    if (Terminated)
        Sysutils::Abort();

    sent = (double(AWorkCount) * 100.0) / xmlString.Length();

    // consider using TThread::Queue() instead so that you don't block
    // the upload waiting for the UI to be updated...
    TThread::Synchronize(this, &UpdateProgressBarInternal);
}

void __fastcall UploadRouteThread::Execute()
{
    tcpClient->Connect();
    try
    {
        NextPacketSize nps;
        nps.PacketID = BasicPacket::DATA_UPLOAD;
        nps.size = xmlString.Length();
        tcpClient->IOHandler->Write(RawToBytes(&nps, sizeof(nps)));

        tcpClient->BeginWork(wmWrite, xmlString.Length());
        tcpClient->IOHandler->Write(RawToBytes(xmlString.c_str(), xmlString.Length()));
        tcpClient->EndWork(wmWrite);

        /* alternatively:
        TIdMemoryBufferStream *strm = new TIdMemoryBufferStream(xmlString.c_str(), xmlString.Length());
        try
        {
            // optional
            tcpClient->IOHandler->SendBufferSize = 256;

            // this calls (Begin|End)Work() internally...
            tcpClient->IOHandler->Write(strm, 0, false);
        }
        __finally
        {
            delete strm;
        }
        */
    }
    __finally
    {
        tcpClient->Disconnect();
    }
}

void __fastcall UploadRouteThread::UpdateProgressBarInternal()
{
    if (!TabbedwithNavigationForm->ProgressBar->Visible)
    {
        TabbedwithNavigationForm->ProgressBar->Visible = true;
        TabbedwithNavigationForm->ProgressBar->Max = 100;
    }

    TabbedwithNavigationForm->ProgressBar->Value = sent;
}

在上表中// Mytable +----+--------------------+---------+ | Id | QuestionOrAnswer | related | +----+--------------------+---------+ | 1 | question1 | 0 | | 2 | answer1 | 1 | | 3 | answer2 | 1 | | 4 | question2 | 0 | | 5 | question3 | 0 | | 6 | answer4 | 5 | | 7 | answer4 | 4 | | 8 | answer4 | 5 | +----+--------------------+---------+表示＆＃34;问题＆＃34;其他任何数字意味着＆＃34;回答＆＃34;。此外，0列中每个问题的ID号都有自己的答案。现在我想知道，我如何选择问题加上所有自己的答案？像这样：

问题1：

related

问题2：

// Mytable
+----+--------------------+---------+
| Id |  QuestionOrAnswer  | related |
+----+--------------------+---------+
| 1  | question1          | 0       |
| 2  | answer1            | 1       |
| 3  | answer2            | 1       |
+----+--------------------+---------+

问题3：

// Mytable
+----+--------------------+---------+
| Id |  QuestionOrAnswer  | related |
+----+--------------------+---------+
| 4  | question2          | 0       |
| 7  | answer4            | 4       |
+----+--------------------+---------+

等等......我怎么能这样做？

Answer 1

试试这个：

select * from Mytable where id = 1 or related = 1

如何选择所有相关行？

1 个答案: