Festlegen großer Datenmengen

Artikel
10/16/2024

Gilt für: SQL Server Azure SQL-Datenbank Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

OLE DB-Treiber herunterladen

Mit dem OLE DB-Treiber für SQL Server können Sie Blobdaten festlegen, indem Sie einen Zeiger an ein Consumerspeicherobjekt übergeben.

Der Consumer erstellt ein Speicherobjekt, das die Daten enthält, und übergibt einen Zeiger auf dieses Speicherobjekt an den Anbieter. Anschließend liest der Anbieter Daten vom Consumerspeicherobjekt und schreibt diese in die BLOB-Spalte.

Zum Übergeben eines Zeigers auf das eigene Speicherobjekt erstellt der Consumer einen Accessor, der den Wert der BLOB-Spalte bindet. Der Consumer ruft dann die IRowsetChange::SetData- oder die IRowsetChange::InsertRow-Methode mit dem Accessor auf, der die BLOB-Spalte bindet. Es wird ein Zeiger auf eine Speicherschnittstelle des Consumerspeicherobjekts übergeben.

In diesem Thema wird die mit folgenden Funktionen verfügbare Funktionalität behandelt:

IRowset:SetData
ICommand::Execute
IRowsetUpdate::Update

So legen Sie große Datenmengen fest

Zum Übergeben eines Zeigers an das eigene Speicherobjekt erstellt der Consumer einen Accessor, der den Wert der BLOB-Spalte bindet, und ruft anschließend die IRowsetChange::SetData -Methode oder die IRowsetChange::InsertRow -Methode auf. So legen Sie BLOB-Daten fest:

Erstellen Sie eine DBOBJECT-Struktur, die beschreibt, wie auf die BLOB-Spalte zugegriffen werden soll. Legen Sie das dwFlag -Element der DBOBJECT-Struktur auf STGM_READ fest, und legen Sie das iid-Element auf IID_ISequentialStream (die verfügbar zu machende Schnittstelle) fest.
Legen Sie die Eigenschaften in der DBPROPSET_ROWSET-Eigenschaftengruppe so fest, dass das Rowset aktualisiert werden kann.
Erstellen Sie mithilfe eines DBBINDING-Strukturarrays einen Satz von Bindungen (eine pro Spalte). Legen Sie das wType-Element in der DBBINDING-Struktur auf DBTYPE_IUNKNOWN fest, und legen Sie das pObject-Element so fest, dass es auf die von Ihnen erstellte DBOBJECT-Struktur zeigt.
Erstellen Sie einen Accessor mithilfe der Bindungsinformationen im DBBINDINGS-Strukturarray.
Rufen Sie GetNextRows auf, um die nächsten Zeilen für das Rowset abzurufen. Rufen Sie GetData auf, um die Daten aus dem Rowset zu lesen.
Erstellen Sie ein Speicherobjekt, das die Daten (sowie den Längenindikator) enthält, und rufen Sie anschließend IRowsetChange::SetData (oder IRowsetChange::InsertRow) mit dem Accessor auf, der die BLOB-Spalte bindet, die die Daten binden soll.

Beispiel

In diesem Beispiel wird gezeigt, wie BLOB-Daten festgelegt werden. Im Beispiel wird eine Tabelle erstellt, ein Beispieldatensatz hinzugefügt, dieser Datensatz im Rowset abgerufen und anschließend der Wert des BLOB-Felds festgelegt.

#define UNICODE  
#define DBINITCONSTANTS  
#define INITGID  
  
#include <windows.h>  
#include <stdio.h>  
#include <stddef.h>  
#include <iostream.h>  
  
#include <oledb.h>  
#include <oledberr.h>  
  
#include <msoledbsql.h>  
  
#define SAFE_RELEASE(pIUnknown) if(pIUnknown) (pIUnknown)->Release();  
HRESULT GetCommandObject(REFIID riid, IUnknown** ppIUnknown);  
HRESULT CreateTable(ICommandText* pICommandText);  
  
class CSeqStream : public ISequentialStream  
{  
public:  
    //Constructors  
    CSeqStream();  
    virtual ~CSeqStream();  
  
    virtual BOOL Seek(ULONG iPos);  
    virtual BOOL Clear();  
    virtual BOOL CompareData(void* pBuffer);  
    virtual ULONG Length()  { return m_cBufSize; };  
  
    virtual operator void* const() { return m_pBuffer; };  
  
    STDMETHODIMP_(ULONG)    AddRef(void);  
    STDMETHODIMP_(ULONG)    Release(void);  
    STDMETHODIMP QueryInterface(REFIID riid, LPVOID *ppv);  
  
    STDMETHODIMP Read(   
            /* [out] */ void __RPC_FAR *pv,  
            /* [in]  */ ULONG cb,  
            /* [out] */ ULONG __RPC_FAR *pcbRead);  
  
    STDMETHODIMP Write(   
            /* [in] */ const void __RPC_FAR *pv,  
            /* [in] */ ULONG cb,  
            /* [out]*/ ULONG __RPC_FAR *pcbWritten);  
  
protected:  
    //Data  
  
private:  
  
    ULONG       m_cRef;         // reference count  
    void*       m_pBuffer;      // buffer  
    ULONG       m_cBufSize;     // buffer size  
    ULONG       m_iPos;         // current index position in the buffer  
};  
  
//class implementation  
  
CSeqStream::CSeqStream()  
{  
    m_iPos         = 0;  
    m_cRef         = 0;  
    m_pBuffer      = NULL;  
    m_cBufSize     = 0;  
  
    //The constructor AddRef's  
    AddRef();  
}  
  
CSeqStream::~CSeqStream()  
{  
    //Shouldn't have any references left  
//    ASSERT(m_cRef == 0);  
    CoTaskMemFree(m_pBuffer);  
}  
  
ULONG    CSeqStream::AddRef(void)  
{  
    return ++m_cRef;  
}  
  
ULONG    CSeqStream::Release(void)  
{  
//    ASSERT(m_cRef);  
  
    if(--m_cRef)  
        return m_cRef;  
  
    delete this;  
    return 0;  
}  
  
HRESULT CSeqStream::QueryInterface(REFIID riid, void** ppv)  
{  
//    ASSERT(ppv);  
    *ppv = NULL;  
  
    if (riid == IID_IUnknown)  
        *ppv = this;  
    if (riid == IID_ISequentialStream)  
        *ppv = this;  
  
    if(*ppv)  
    {  
        ((IUnknown*)*ppv)->AddRef();  
        return S_OK;  
    }  
  
    return E_NOINTERFACE;  
}  
  
BOOL CSeqStream::Seek(ULONG iPos)  
{  
    // Make sure the desired position is within the buffer.  
//    ASSERT(iPos == 0 || iPos < m_cBufSize);  
  
    // Reset the current buffer position.  
    m_iPos = iPos;  
    return TRUE;  
}  
  
BOOL CSeqStream::Clear()  
{  
    //Frees the buffer  
    m_iPos         = 0;  
    m_cBufSize     = 0;  
  
    CoTaskMemFree(m_pBuffer);  
    m_pBuffer = NULL;  
  
    return TRUE;  
}  
  
BOOL CSeqStream::CompareData(void* pBuffer)  
{  
//    ASSERT(pBuffer);  
  
    // Quick and easy way to compare user buffer with the stream.  
    return memcmp(pBuffer, m_pBuffer, m_cBufSize)==0;  
}  
  
HRESULT CSeqStream::Read(void *pv, ULONG cb, ULONG* pcbRead)  
{  
    //Parameter checking  
    if(pcbRead)  
        *pcbRead = 0;  
  
    if(!pv)  
        return STG_E_INVALIDPOINTER;  
  
    if(cb == 0)  
        return S_OK;  
  
    // Actual code.  
    ULONG cBytesLeft = m_cBufSize - m_iPos;  
    ULONG cBytesRead = cb > cBytesLeft ? cBytesLeft : cb;  
  
    // If no more bytes to retrieve return.  
    if(cBytesLeft == 0)  
        return S_FALSE;   
  
    // Copy to users buffer the number of bytes requested or remaining.  
    memcpy_s(pv, sizeof(pv), (void*)((BYTE*)m_pBuffer + m_iPos), cBytesRead);  
    m_iPos += cBytesRead;  
  
    if(pcbRead)  
        *pcbRead = cBytesRead;  
  
    if(cb != cBytesRead)  
        return S_FALSE;   
  
    return S_OK;  
}  
  
HRESULT CSeqStream::Write(const void *pv, ULONG cb, ULONG* pcbWritten)  
{  
    // Parameter checking.  
    if(!pv)  
        return STG_E_INVALIDPOINTER;  
  
    if(pcbWritten)  
        *pcbWritten = 0;  
  
    if(cb == 0)  
        return S_OK;  
  
    // Enlarge the current buffer.  
    m_cBufSize += cb;  
  
    // Need to append to the end of the stream.  
    m_pBuffer = CoTaskMemRealloc(m_pBuffer, m_cBufSize);  
    memcpy_s((void*)((BYTE*)m_pBuffer + m_iPos), sizeof((void*)((BYTE*)m_pBuffer + m_iPos)), pv, cb);  
    // m_iPos += cb;  
  
    if(pcbWritten)  
        *pcbWritten = cb;  
  
    return S_OK;  
}  
//...........................................................  
void main()  
{  
    CoInitialize(NULL);  
  
    DBOBJECT ObjectStruct;  
    ObjectStruct.dwFlags = STGM_READ;  
    ObjectStruct.iid     = IID_ISequentialStream;  
  
    struct BLOBDATA  
    {  
        DBSTATUS            dwStatus;     
        DWORD               dwLength;   
        ISequentialStream*  pISeqStream;  
    };  
  
    BLOBDATA BLOBGetData;  
    BLOBDATA BLOBSetData;  
  
    const ULONG cBindings = 1;  
    DBBINDING rgBindings[cBindings];   
    HRESULT hr = S_OK;  
    IAccessor*          pIAccessor          = NULL;  
    ICommandText*       pICommandText       = NULL;  
    ICommandProperties* pICommandProperties = NULL;  
    IRowsetChange*      pIRowsetChange      = NULL;  
    IRowset*            pIRowset            = NULL;  
    CSeqStream*         pMySeqStream        = NULL;  
    ULONG cRowsObtained = 0;  
    HACCESSOR hAccessor = DB_NULL_HACCESSOR;  
    DBBINDSTATUS rgBindStatus[cBindings];  
    HROW* rghRows = NULL;  
    const ULONG cPropSets = 1;  
    DBPROPSET   rgPropSets[cPropSets];  
    const ULONG cProperties = 1;  
    DBPROP      rgProperties[cProperties];  
    const ULONG cBytes = 10;  
    BYTE        pBuffer[cBytes];  
    ULONG       cBytesRead = 0;  
  
    BYTE pReadData[cBytes];  //read BLOB data in this array  
    memset(pReadData, 0xAA, cBytes);  
  
    BYTE pWriteData[cBytes];  //write BLOB data from this array  
    memset(pWriteData, 'D', cBytes);  
  
    // Get the Command object.  
    hr = GetCommandObject(IID_ICommandText,   
                          (IUnknown**)&pICommandText);  
    if (FAILED(hr))  
    {  
        cout << "Failed to get ICommandText interface.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    // Create table with image column and index.  
    hr = CreateTable(pICommandText);  
    if (FAILED(hr))  
    {  
        cout << "Failed to create table.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    /*  
    Set the DBPROPSET structure.  It is used to pass an array   
    of DBPROP structures to SetProperties().  
    */  
    rgPropSets[0].guidPropertySet = DBPROPSET_ROWSET;  
    rgPropSets[0].cProperties = cProperties;  
    rgPropSets[0].rgProperties = rgProperties;  
  
    // Now set properties in the property group (DBPROPSET_ROWSET).  
    rgPropSets[0].rgProperties[0].dwPropertyID = DBPROP_UPDATABILITY;  
    rgPropSets[0].rgProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;  
    rgPropSets[0].rgProperties[0].dwStatus = DBPROPSTATUS_OK;  
    rgPropSets[0].rgProperties[0].colid = DB_NULLID;  
    rgPropSets[0].rgProperties[0].vValue.vt = VT_I4;  
    V_I4(&rgPropSets[0].rgProperties[0].vValue) = DBPROPVAL_UP_CHANGE;  
  
    // Set the rowset properties.  
    hr = pICommandText->QueryInterface(IID_ICommandProperties,  
                            (void **)&pICommandProperties);  
    if (FAILED(hr))  
    {  
        cout << "Failed to get ICommandProperties to set rowset properties.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
    hr = pICommandProperties->SetProperties(cPropSets, rgPropSets);  
    if (FAILED(hr))  
    {  
        cout << "Execute failed to set rowset properties.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    // Execute a command (SELECT * FROM TestISeqStream).  
    hr = pICommandText->SetCommandText(DBGUID_DBSQL,  
                                       L"SELECT * FROM TestISeqStream");  
    if (FAILED(hr))  
    {  
        cout << "Failed to set command text SELECT * FROM.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    hr = pICommandText->Execute(NULL, IID_IRowsetChange, NULL, NULL,  
                                (IUnknown**)&pIRowsetChange);  
    if (FAILED(hr))  
    {  
        cout << "Failed to execute the command SELECT * FROM.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    // Fill the DBBINDINGS array.  
    rgBindings[0].iOrdinal = 2; //ordinal position  
    rgBindings[0].obValue = offsetof(BLOBDATA, pISeqStream);  
    rgBindings[0].obLength = offsetof(BLOBDATA, dwLength);  
    rgBindings[0].obStatus = offsetof(BLOBDATA, dwStatus);  
    rgBindings[0].pTypeInfo = NULL;  
    rgBindings[0].pObject = &ObjectStruct;  
    rgBindings[0].pBindExt = NULL;  
    rgBindings[0].dwPart =  DBPART_VALUE | DBPART_STATUS | DBPART_LENGTH;  
    rgBindings[0].dwMemOwner = DBMEMOWNER_CLIENTOWNED;  
    rgBindings[0].eParamIO = DBPARAMIO_NOTPARAM;  
    rgBindings[0].cbMaxLen = 0;   
    rgBindings[0].dwFlags = 0;  
    rgBindings[0].wType = DBTYPE_IUNKNOWN;  
    rgBindings[0].bPrecision = 0;  
    rgBindings[0].bScale = 0;  
  
    // Create an accessor using the binding information.  
    hr = pIRowsetChange->QueryInterface(IID_IAccessor,   
                                        (void**)&pIAccessor);  
    if (FAILED(hr))  
    {  
        cout << "Failed to get IAccessor interface.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    hr = pIAccessor->CreateAccessor(DBACCESSOR_ROWDATA,  
                                    cBindings,  
                                    rgBindings,   
                                    sizeof(BLOBDATA),  
                                    &hAccessor,  
                                    rgBindStatus);  
    if (FAILED(hr))  
    {  
        cout << "Failed to create an accessor.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if   
  
    // Now get the first row.  
    hr = pIRowsetChange->QueryInterface(IID_IRowset,   
                                        (void **)&pIRowset);  
    if (FAILED(hr))  
    {  
        cout << "Failed to get IRowset interface.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    hr = pIRowset->GetNextRows(NULL,   
                               0,   
                               1,   
                               &cRowsObtained,   
                               &rghRows);  
  
    hr = pIRowset->GetData(rghRows[0],   
                           hAccessor,   
                           &BLOBGetData);  
  
    // Verify the retrieved data, only if data is not null.  
    if (BLOBGetData.dwStatus == DBSTATUS_S_ISNULL)  
    {  
        // Process null data.  
        cout << "Provider returned a null value.\n";  
    } else if(BLOBGetData.dwStatus == DBSTATUS_S_OK)   
      // Provider returned a nonNULL value.  
    {  
        BLOBGetData.pISeqStream->Read(  
                                    pBuffer,   
                                    cBytes,   
                                    &cBytesRead);  
        if(memcmp(pBuffer, pReadData, cBytes) != 0)  
        {  
            //cleanup   
         }  
  
        SAFE_RELEASE(BLOBGetData.pISeqStream);  
    }  
  
    // Set up data for SetData.  
    pMySeqStream = new CSeqStream();  
  
    /*  
    Put data in to the ISequentialStream object   
    for the provider to write.  
    */  
    pMySeqStream->Write(pWriteData,   
                        cBytes,   
                        NULL);  
  
    BLOBSetData.pISeqStream = (ISequentialStream*)pMySeqStream;  
    BLOBSetData.dwStatus    = DBSTATUS_S_OK;  
    BLOBSetData.dwLength    = pMySeqStream->Length();  
  
    // Set the data.  
    hr = pIRowsetChange->SetData(rghRows[0],   
                                 hAccessor,   
                                 &BLOBSetData);  
        if (FAILED(hr))  
    {  
        cout << "Failed to set data.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    hr = pIAccessor->ReleaseAccessor(hAccessor, NULL);  
    if (FAILED(hr))  
    {  
        cout << "Failed to release accessor.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
    hr = pIRowset->ReleaseRows(cRowsObtained,   
                            rghRows,   
                            NULL,   
                            NULL,   
                            NULL);  
    if (FAILED(hr))  
    {  
        cout << "Failed to release rows.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
Exit:  
    // Free up all allocated memory and release interface pointers.  
  
    CoUninitialize();  
} //end main.  
//..........................................................  
HRESULT GetCommandObject(REFIID riid, IUnknown** ppIUnknown)  
{  
    HRESULT hr = S_OK;  
  
    // Local interface pointers, until a connection is made.  
    IDBInitialize* pIDBInitialize = NULL;  
    IDBProperties*  pIDBProperties = NULL;  
    IDBCreateSession* pIDBCreateSession = NULL;  
    IDBCreateCommand* pIDBCreateCommand = NULL;  
  
    const ULONG cPropSets = 1;  
    DBPROPSET rgPropSets[cPropSets];  
  
    const ULONG cProperties = 4;  
    DBPROP rgProperties[cProperties];  
  
    /*  
    Initialize the property values needed to   
    establish the connection.  
    */  
    for(ULONG i = 0; i < 4; i++)  
        VariantInit(&rgProperties[i].vValue);  
  
    // Server name.  
    rgProperties[0].dwPropertyID = DBPROP_INIT_DATASOURCE;  
    rgProperties[0].vValue.vt = VT_BSTR;  
    rgProperties[0].vValue.bstrVal =   
                    SysAllocString(L"server");  
    rgProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;  
    rgProperties[0].colid = DB_NULLID;  
  
    // Database.  
    rgProperties[1].dwPropertyID = DBPROP_INIT_CATALOG;  
    rgProperties[1].vValue.vt = VT_BSTR;  
    rgProperties[1].vValue.bstrVal =   
                    SysAllocString(L"pubs");  
    rgProperties[1].dwOptions = DBPROPOPTIONS_REQUIRED;  
    rgProperties[1].colid = DB_NULLID;  
  
    // Username (login).  
    rgProperties[2].dwPropertyID = DBPROP_AUTH_USERID;  
    rgProperties[2].vValue.vt = VT_BSTR;  
    rgProperties[2].vValue.bstrVal =   
                    SysAllocString(L"login");  
    rgProperties[2].dwOptions = DBPROPOPTIONS_REQUIRED;  
    rgProperties[2].colid = DB_NULLID;  
  
    // Password.  
    rgProperties[3].dwPropertyID = DBPROP_AUTH_PASSWORD;  
    rgProperties[3].vValue.vt = VT_BSTR;  
    rgProperties[3].vValue.bstrVal =   
                    SysAllocString(L"password");  
    rgProperties[3].dwOptions = DBPROPOPTIONS_REQUIRED;  
    rgProperties[3].colid = DB_NULLID;  
  
    /*  
    Now that the properties are set, construct the DBPROPSET   
    structure (rgInitPropSet).  The DBPROPSET structure is used   
    to pass an array of DBPROP structures (InitProperties) to the   
    SetProperties method.  
    */  
    rgPropSets[0].guidPropertySet   = DBPROPSET_DBINIT;  
    rgPropSets[0].cProperties       = cProperties;  
    rgPropSets[0].rgProperties      = rgProperties;  
  
    // Get the IDBInitialize interface.  
    hr = CoCreateInstance(CLSID_MSOLEDBSQL,   
                            NULL,   
                            CLSCTX_INPROC_SERVER,  
                            IID_IDBInitialize,   
                            (void**)&pIDBInitialize);  
    if(FAILED(hr))  
    {  
        cout << "Failed to get IDBInitialize interface.\n";  
        // Release any references and return.  
        goto Exit;  
  
    } //end if  
  
    // Set initialization properties.  
    hr = pIDBInitialize->QueryInterface(IID_IDBProperties,  
                                        (void **)&pIDBProperties);  
    if(FAILED(hr))  
    {  
        cout << "Failed to get IDBProperties interface.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
    hr = pIDBProperties->SetProperties(cPropSets, rgPropSets);  
     if(FAILED(hr))  
    {  
        cout << "Failed to set properties for DBPROPSET_DBINIT.\n";  
        // Release any references and return.  
        goto Exit;  
    } //end if  
  
     hr = pIDBInitialize->Initialize();  
      if(FAILED(hr))  
    {  
        cout << "Failed to initialize.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
    //Create a session object.  
      hr = pIDBInitialize->QueryInterface(  
                                IID_IDBCreateSession,  
                                (void **)&pIDBCreateSession);  
       if(FAILED(hr))  
    {  
        cout << "Failed to get pIDBCreateSession interface.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
       hr = pIDBCreateSession->CreateSession(  
                                    NULL,   
                                    IID_IDBCreateCommand,  
                                    (IUnknown**)&pIDBCreateCommand);  
     if(FAILED(hr))  
    {  
        cout << "Failed to create session object.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
     // Get the CommandText object.  
     hr = pIDBCreateCommand->CreateCommand(  
                                    NULL,   
                                    riid,   
                                    (IUnknown**)ppIUnknown);  
     if(FAILED(hr))  
    {  
        cout << "Failed to create CommandText object.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
     return hr;  
Exit:  
    // Free up all allocated memory and release interface pointers.  
     return hr;  
  
} //end function  
//...............................................................  
HRESULT CreateTable(ICommandText* pICommandText)  
{  
    HRESULT hr = S_OK;  
  
    // Drop the xisting table.  
    hr = pICommandText->SetCommandText(  
                            DBGUID_DBSQL,  
                            L"DROP TABLE TestISeqStream");  
    if(FAILED(hr))  
    {  
        cout << "Failed to set command text DROP TABLE.\n";  
        // Release any references and return.  
        goto Exit;  
  
    } //end if  
  
    hr = pICommandText->Execute(NULL, IID_NULL, NULL, NULL, NULL);  
    if(FAILED(hr))  
    {  
        cout << "Failed to drop the table.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
    // Create a new table.  
    hr = pICommandText->SetCommandText(DBGUID_DBSQL,  
         L"CREATE TABLE TestISeqStream (col1 int,col2 image)");  
    if(FAILED(hr))  
    {  
        cout << "Failed to set command text CREATE TABLE.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
    hr = pICommandText->Execute(NULL, IID_NULL, NULL, NULL, NULL);  
    if(FAILED(hr))  
    {  
        cout << "Failed to create new table.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
    // Insert one row into table.  
    hr = pICommandText->SetCommandText(DBGUID_DBSQL,  
    L"INSERT INTO TestISeqStream(col1,col2) VALUES (1,0xAAAAAAAAAAAAAAAAA)");  
    if(FAILED(hr))  
    {  
        cout << "Failed to set command text INSERT INTO.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
    hr = pICommandText->Execute(NULL, IID_NULL, NULL, NULL, NULL);  
    if(FAILED(hr))  
    {  
        cout << "Failed to insert record in the table.\n";  
        // Release any references and return.  
        goto Exit;  
    } // end if  
  
Exit:  
    // Free up all allocated memory and release interface pointers.  
     return hr;  
  
} //end function

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