public async Task AnonymiseCustomerData() { var customers = await GetAllCustomers(); var collectionUri = _documentDbHelper.CreateDestinationCustomerDocumentCollectionUri(); var client = _databaseClient.CreateDestinationDocumentClient(); var databaseName = "customers"; var databaseCollection = "customers-anonymised"; client.CreateDocumentCollectionIfNotExistsAsync( UriFactory.CreateDatabaseUri(databaseName), new DocumentCollection { Id = databaseCollection }). GetAwaiter() .GetResult(); foreach (var cust in customers) { cust.FamilyName = _utils.RandomString() + cust.FamilyName + _utils.RandomString(); cust.GivenName = _utils.RandomString() + cust.GivenName + _utils.RandomString(); cust.DateofBirth = _utils.RandomDate(); var response = await client.CreateDocumentAsync(collectionUri, cust); } }