from google.cloud import bigquery

start_index = 10
query_job = bigquery.Client().query(
    "SELECT word FROM `bigquery-public-data.samples.shakespeare` LIMIT 50;",
    job_id_prefix="test_query_w_start_index_",
)

# check the normal row iterator
result = query_job.result(start_index=start_index, page_size=10)
print(result.total_rows)        
print(len(list(result)))   # returns 50 not 40

# iterate over pages
result = query_job.result(start_index=start_index, page_size=10)
print(result.total_rows)        
print(sum(len(list(page)) for page in result.pages))  # returns 50 not 40