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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.cpp  
// compile with: /EHsc  
#import "msadox.dll" no_namespace  
  
#include "iostream"  
using namespace std;  
  
// Function declarations  
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};  
void ClusteredX();  
  
int main() {  
   if ( FAILED(::CoInitialize(NULL) ) )  
      return -1;  
  
   ClusteredX();  
   ::CoUninitialize();  
}  
  
void ClusteredX() {  
   HRESULT hr = S_OK;  
  
   // Define ADOX object pointers, initialize pointers. These are in ADODB 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:\\Northwind.mdb';");  
  
      // 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;  
         }  
      }  
   }  
   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 occurred in ClusteredX...."<< endl;  
   }  
}  

See Also

Clustered Property (ADOX)
Index Object (ADOX)