Clustered Property Example (VC++)

Microsoft ActiveX Data Objects (ADO)

ADOX 2.5

Clustered Property Example (VC++)

This example demonstrates the Clustered property of an Index. Note that Microsoft Jet databases do not support clustered indexes, so this example will return False for the Clustered property of all indexes in the Northwind database.

// BeginClusteredCpp
#import "c:\Program Files\Common Files\system\ado\msadox.dll" \
    no_namespace

#include "iostream.h"
#include "stdio.h"
#include "conio.h"

//Function declarations
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};
void ClusteredX(void);

//////////////////////////////////////////////////////////
//                                                      //
//     Main Function                                    //
//                                                      //
//////////////////////////////////////////////////////////
void main()
{
    if(FAILED(::CoInitialize(NULL)))
        return;

    ClusteredX();

    ::CoUninitialize();
}

//////////////////////////////////////////////////////////
//                                                      //
//       ClusteredX Function                            //
//                                                      //
//////////////////////////////////////////////////////////
void ClusteredX()
{
    HRESULT hr = S_OK;

    // Define ADOX object pointers.
    // Initialize pointers on define.
    // These are in the ADOX::  namespace.
    _CatalogPtr m_pCatalog = NULL;
    _TablePtr m_pTable = NULL;
    _IndexPtr m_pIndex = NULL;

    //Define other variables here
    _variant_t vIndex;
    try
    {
        TESTHR(hr = m_pCatalog.CreateInstance(__uuidof(Catalog)));

        // Connect to the catalog.
        m_pCatalog->PutActiveConnection(
            "Provider='Microsoft.JET.OLEDB.4.0';data source="
            "'c:\\Program Files\\Microsoft Office\\Office\\Samples"
            "\\Northwind.mdb';");

        int iLineCnt = 1; 
        //Enumerate Tables.
        for(short iTable = 0;iTable < m_pCatalog->Tables->Count;iTable++)
        {
            vIndex = iTable;
            m_pTable = m_pCatalog->Tables->GetItem(vIndex);

            //Enumerate Indexes.
            for(short iIndex = 0;iIndex < m_pTable->Indexes->Count;
                iIndex++)
            {
                vIndex = iIndex;
                m_pIndex = m_pTable->Indexes->GetItem(vIndex);
                cout << m_pTable->Name << "   " ;
                cout << m_pIndex->Name << "   " << (m_pIndex->
                    GetClustered() ? "True" : "False") << endl;

                 if (iLineCnt%15 == 0)
                {
                    printf("\nPress any key to continue...\n");
                    getch();
                }
                iLineCnt++;
            }
        }
    }
    catch(_com_error &e)
    {
        // Notify the user of errors if any.
        _bstr_t bstrSource(e.Source());
        _bstr_t bstrDescription(e.Description());

        printf("\n\tSource :  %s \n\tdescription : %s \n ",
            (LPCSTR)bstrSource,(LPCSTR)bstrDescription);
    }
    catch(...)
    {
        cout << "Error occured in ClusteredX...."<< endl;
    }
}
// EndClusteredCpp

See Also

Clustered Property | Index Object

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