ADOX - Access Table Creation With Nullable Columns.

I need to programatically create a mdb file which will contain nullable columns. I am using C++ with ADOX for the table creation and ADO to perform the table update.

Although ADOX seems to create the table ok, Table->Columns->Appends does not set the fields as adColNullable as expected.

When I insert data using ADO::Recordset->AddNew the following error occurs :- "The field 'MyTable.Column 2' cannot contain a Null value because the Required property for this field is set to True. Enter a value in this field."

Am I on the right tracks here or do I need to adopt a different approach?

Code block to illustrate the problem :-



Code Block
ADOX::_CatalogPtr m_pCatalog;
ADOX::_TablePtr m_pTable;
ADOX::_ColumnPtr m_pCol1;
ADOX::_ColumnPtr m_pCol2;
ADODB::_ConnectionPtr m_pConn;
ADODB::_RecordsetPtr m_pRs;
//ADOX - Create Data Source
_bstr_t strcnn(("Provider='Microsoft.JET.OLEDB.4.0';Data source = C:\test.mdb"));
m_pCatalog.CreateInstance(__uuidof (ADOX::Catalog));
m_pCatalog->Create(strcnn);

m_pTable.CreateInstance(__uuidof(ADOX::Table));
m_pTable->PutName("MyTable");

m_pCol1.CreateInstance(__uuidof(ADOX::Column));
m_pCol1->Name = "Column 1";
m_pCol1->Type = ADOX::adVarWChar;
m_pCol1->DefinedSize = 24;
m_pCol1->Attributes = ADOX::adColNullable;
m_pTable->Columns->Append(m_pCol1->Name, ADOX::adVarWChar, 24);

m_pCol2.CreateInstance(__uuidof(ADOX::Column));
m_pCol2->Name = "Column 2";
m_pCol2->Type = ADOX::adVarWChar;
m_pCol2->DefinedSize = 24;
m_pCol2->Attributes = ADOX::adColNullable;
m_pTable->Columns->Append(m_pCol2->Name, ADOX::adVarWChar, 24);

m_pCatalog->Tables->Append(_variant_t((IDispatch *)m_pTable));


//ADO - Data Access
m_pConn.CreateInstance (__uuidof(ADODB::Connection));
m_pConn->Open(strcnn,_bstr_t(""),_bstr_t(""),ADODB::adOpenUnspecified);
m_pRs.CreateInstance(__uuidof(ADODB::Recordset));
m_pRs->Open("MyTable", _variant_t((IDispatch *)m_pConn,true),ADODB::adOpenKeyset, ADODB::adLockOptimistic, ADODB::adCmdTable);

// Define a SafeArray that contains field names.
SAFEARRAY * psaFields;
SAFEARRAYBOUND aDimFields[1];
aDimFields[0].lLbound = 0;
aDimFields[0].cElements = 1;
psaFields = SafeArrayCreate(VT_VARIANT, 1, aDimFields);

// Create a SafeArray for values.
SAFEARRAY * psaValues;
SAFEARRAYBOUND aDimValues[1];
aDimValues[0].lLbound = 0;
aDimValues[0].cElements = 1;
psaValues = SafeArrayCreate(VT_VARIANT, 1, aDimValues);
long ix[1];
_variant_t var;

//Insert Data
ix[0] = 0;
var = "Column 1";
SafeArrayPutElement(psaFields, ix, (void*) (VARIANT *) (&var));
ix[0] = 0;
var = "test data row 1 col 1 Only";
SafeArrayPutElement(psaValues, ix, (void*)(VARIANT *) &var);
_variant_t vtFields, vtValues;
vtFields.vt = VT_ARRAY | VT_VARIANT;
vtValues.vt = VT_ARRAY | VT_VARIANT;
vtFields.parray = psaFields;
vtValues.parray = psaValues;

m_pRs->AddNew(vtFields, vtValues); //!! Fails Here !!

m_pRs->Update();
m_pRs->Close();
m_pConn->Close();