Procedura: Creazione di un database tramite OLE DB (a livello di programmazione)
Il provider OLE DB per SQL Server 2005 Compact Edition (SQL Server Compact Edition) espone l'interfaccia IDBDataSourceAdmin, tramite cui è possibile creare e gestire database di SQL Server Compact Edition. Per creare un nuovo database, è possibile specificarne il nome utilizzando la proprietà DBPROP_INIT_DATASOURCE.
Per ulteriori informazioni, vedere Creazione di database con OLE DB.
Esempio
Nell'esempio seguente viene illustrato come creare un database crittografato utilizzando il provider OLE DB per SQL Server Compact Edition. Per creare un database standard o protetto dalla sola password, rimuovere le strutture DBPROP non necessarie.
// Object declarations
HRESULT hr = NOERROR;
DBPROPSET dbpropset[2];
DBPROP dbprop[1]; // Property array to initialize the provider.
DBPROP sscedbprop[2]; // Property array for SSCE security properties
INT i = 0;
IDBDataSourceAdmin *pIDBDataSourceAdmin = NULL;
IUnknown *pIUnknownSession = NULL;
// Create an instance of the OLE DB provider.
hr = CoCreateInstance( CLSID_SQLSERVERCE_3_0, 0, CLSCTX_INPROC_SERVER,
IID_IDBDataSourceAdmin, (void**)& pIDBDataSourceAdmin);
if(FAILED(hr))
{
goto Exit;
}
// Initialize property structures.
VariantInit(&dbprop[0].vValue);
for (int i = 0; i < sizeof(sscedbprop) / sizeof(sscedbprop[0]); i++)
{
VariantInit(&sscedbprop[i].vValue);
}
// Specify the property with name of the database.
dbprop[0].dwPropertyID = DBPROP_INIT_DATASOURCE;
dbprop[0].dwOptions = DBPROPOPTIONS_REQUIRED;
dbprop[0].vValue.vt = VT_BSTR;
dbprop[0].vValue.bstrVal = SysAllocString(L"NewDatabase.sdf");
if(NULL == dbprop[0].vValue.bstrVal)
{
hr = E_OUTOFMEMORY;
goto Exit;
}
// Specify the property for encryption.
sscedbprop[0].dwPropertyID = DBPROP_SSCE_ENCRYPTDATABASE;
sscedbprop[0].dwOptions = DBPROPOPTIONS_REQUIRED;
sscedbprop[0].vValue.vt = VT_BOOL;
sscedbprop[0].vValue.boolVal = VARIANT_TRUE;
// Specify the password.
sscedbprop[1].dwPropertyID = DBPROP_SSCE_DBPASSWORD;
sscedbprop[1].dwOptions = DBPROPOPTIONS_REQUIRED;
sscedbprop[1].vValue.vt = VT_BSTR;
sscedbprop[1].vValue.bstrVal = SysAllocString(L"mypassword");
if(NULL == sscedbprop[1].vValue.bstrVal)
{
hr = E_OUTOFMEMORY;
goto Exit;
}
// Initialize the property sets.
dbpropset[0].guidPropertySet = DBPROPSET_DBINIT;
dbpropset[0].rgProperties = dbprop;
dbpropset[0].cProperties = sizeof(dbprop)/sizeof(dbprop[0]);
dbpropset[1].guidPropertySet = DBPROPSET_SSCE_DBINIT ;
dbpropset[1].rgProperties = sscedbprop;
dbpropset[1].cProperties = sizeof(sscedbprop)/sizeof(sscedbprop[0]);
// Create and initialize the database.
hr = pIDBDataSourceAdmin->CreateDataSource(sizeof(dbpropset)/sizeof(dbpropset[0]),
dbpropset, NULL, IID_IUnknown, &pIUnknownSession);
if(FAILED(hr))
{
goto Exit;
}
// At this point, the new encrypted database is created.
Exit:
// Do cleanup tasks here.
return;