Problem With Simple Microsoft.SQLSERVER.CE.OLEDB.3.5 Update Query Using Native Code / ATL

   I am trying to write a "simple" UPDATE query using the following native code that I have cobbled together from examples. The code compiles and runs without error and the results indicate that several rows were updated but the changes were not written to the DB. What in the #$%^#@% amd I doing wrong ?? Thanks for any help. TB

#define ROUNDUP(size) ROUNDUP_(size, 8)
void MyExample()
{
	HRESULT hr = NOERROR; 
	IDBCreateCommand * pIDBCrtCmd = NULL;
	ICommandText * pICmdText = NULL;
	ICommandPrepare * pICmdPrepare = NULL;
	ICommandWithParameters * pICmdWParams = NULL;
	ULONG ulNumCols;
	IAccessor * pIAccessor = NULL;
	ULONG cParams;
	DBPARAMINFO * rgParamInfo = NULL;
	WCHAR* pNamesBuffer = NULL;
	BYTE * pData = NULL; 	
	ULONG cbRowSize;
	DBPARAMS params;
	HACCESSOR hAccessor;

	hr = CoInitialize(0);

	DBBINDING* rgBindings = (DBBINDING*)CoTaskMemAlloc( sizeof(DBBINDING) * 2 );

	memset( rgBindings, 0, sizeof(DBBINDING) * 2 );
	
    CComPtr<IDBInitialize> spIDBInitialize;
	hr = spIDBInitialize.CoCreateInstance(OLESTR("Microsoft.SQLSERVER.CE.OLEDB.3.5"));

    CComPtr<IDBProperties> spIDBProperties;
    hr = spIDBInitialize->QueryInterface(IID_IDBProperties, (void**) &spIDBProperties);

	CComVariant varDataSource(OLESTR("MySQLCEDB.sdf"));

	CComVariant varPassword(OLESTR("MyPword"));

	DBPROP sscedbprop = { DBPROP_SSCE_DBPASSWORD, DBPROPOPTIONS_REQUIRED, 0, DB_NULLID, varPassword };
	DBPROP dbprop = { DBPROP_INIT_DATASOURCE, DBPROPOPTIONS_REQUIRED, 0, DB_NULLID, varDataSource };
	
	DBPROPSET dbpropset[2];

	// Initialize property set.
	dbpropset[0].guidPropertySet = DBPROPSET_DBINIT;
	dbpropset[0].rgProperties = &dbprop;
	dbpropset[0].cProperties = 1;

	dbpropset[1].guidPropertySet = DBPROPSET_SSCE_DBINIT;
	dbpropset[1].rgProperties = &sscedbprop;
	dbpropset[1].cProperties = 1;

	hr = spIDBProperties->SetProperties(2, dbpropset);
    hr = spIDBInitialize->Initialize();

    CComPtr<IDBCreateSession> spIDBCreateSession;
    hr = spIDBInitialize->QueryInterface(IID_IDBCreateSession, (void**) &spIDBCreateSession);

	hr = spIDBCreateSession->CreateSession(NULL,IID_IDBCreateCommand,(IUnknown**)&pIDBCrtCmd);
	hr = pIDBCrtCmd->CreateCommand(NULL,IID_ICommandWithParameters, (IUnknown**)&pICmdWParams); 
	hr = pICmdWParams->QueryInterface( IID_ICommandText,(void**)&pICmdText);
	hr = pICmdWParams->QueryInterface( IID_ICommandPrepare,(void**)&pICmdPrepare);
	LPCTSTR wSQLString = L"UPDATE MyTable SET Name = ? WHERE Name = ?";
	hr = pICmdText->SetCommandText( DBGUID_DBSQL, wSQLString );

	hr = pICmdPrepare->Prepare(1);
	hr = pICmdWParams->GetParameterInfo(&cParams, &rgParamInfo, &pNamesBuffer);
	hr = pICmdText->QueryInterface( IID_IAccessor, (void**)&pIAccessor);

	
	DWORD dwOffset = 0;

	rgBindings[0].iOrdinal = 1;
	rgBindings[0].obStatus = dwOffset;
	rgBindings[0].obLength = dwOffset+sizeof(DBSTATUS);
	rgBindings[0].obValue = dwOffset+sizeof(DBSTATUS); + sizeof(ULONG);
	rgBindings[0].pTypeInfo = NULL;
	rgBindings[0].pObject = NULL;
	rgBindings[0].pBindExt = NULL;
	rgBindings[0].dwPart = DBPART_VALUE | DBPART_STATUS | DBPART_LENGTH;
	rgBindings[0].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
	rgBindings[0].eParamIO = DBPARAMTYPE_INPUTOUTPUT;
	rgBindings[0].cbMaxLen = sizeof(WCHAR) * 100;
	rgBindings[0].dwFlags = 0;
	rgBindings[0].wType = DBTYPE_WSTR;
	rgBindings[0].bPrecision = 0;
	rgBindings[0].bScale = 0;

	dwOffset = rgBindings[0].cbMaxLen + rgBindings[0].obValue;
	dwOffset = ROUNDUP( dwOffset );
	rgBindings[1].iOrdinal = 2;
	rgBindings[1].obStatus = dwOffset;
	rgBindings[1].obLength = dwOffset + sizeof(DBSTATUS);
	rgBindings[1].obValue = dwOffset + sizeof(DBSTATUS) + sizeof(ULONG);
	rgBindings[1].pTypeInfo = NULL;
	rgBindings[1].pObject = NULL;
	rgBindings[1].pBindExt = NULL;
	rgBindings[1].dwPart = DBPART_VALUE | DBPART_STATUS | DBPART_LENGTH;
	rgBindings[1].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
	rgBindings[1].eParamIO = DBPARAMTYPE_INPUTOUTPUT;
	rgBindings[1].cbMaxLen = sizeof(WCHAR) * 100;
	rgBindings[1].dwFlags = 0;
	rgBindings[1].wType = DBTYPE_WSTR;
	rgBindings[1].bPrecision = 0;
	rgBindings[1].bScale = 0;
	cbRowSize = rgBindings[1].obValue + rgBindings[1].cbMaxLen;
	hr = pIAccessor->CreateAccessor( DBACCESSOR_PARAMETERDATA, 2, rgBindings, cbRowSize, &hAccessor, NULL );

	pData = (BYTE*) malloc( cbRowSize );
	
	memset( pData, 0, cbRowSize );

	WCHAR* new_value =  L"NewName";
	WCHAR* old_val = L"OldName";
	*(DBSTATUS*)(pData + rgBindings[0].obStatus) = DBSTATUS_S_OK;
	wcscpy( (WCHAR*)(pData + rgBindings[0].obValue), new_value );	
	*(ULONG*)(pData + rgBindings[0].obLength) = sizeof(WCHAR) * wcslen( new_value );	
	*(DBSTATUS*)(pData + rgBindings[1].obStatus) = DBSTATUS_S_OK;	
	wcscpy( (WCHAR*)(pData + rgBindings[1].obValue), old_val );	
	*(ULONG*)(pData + rgBindings[1].obLength) = sizeof(WCHAR) * wcslen( old_val );	
	params.pData = pData;
	params.cParamSets = 2;
	params.hAccessor = hAccessor;
	DBROWCOUNT row_count;
	hr = pICmdText->Execute( NULL, IID_NULL, &params, &row_count, NULL );
	// when I run this, row_count is set to 5 indicating 5 rows were affected but the changes
	// do not appear in the DB file.
	// What am I doing wrong ?????

}