Example read and write to BigQuery using Python

connect_db_bq_example.py

from google.cloud import bigquery
import datetime

def add_items_to_bigquery(name, description, in_cloud=True):
  print("Adding items to BigQuery")
  # Instantiates a client
  bigquery_client = bigquery.Client()

  # Prepares a reference to the dataset
  dataset_ref = bigquery_client.dataset('universitas_library')

  table_ref = dataset_ref.table('projects')
  table = bigquery_client.get_table(table_ref)  # API call
  new_date = datetime.datetime.now()

  rows_to_insert = [
    (new_date, name, description, True)
  ]
  print("Adding the following item")
  print(rows_to_insert)
  errors = bigquery_client.insert_rows(table, rows_to_insert)  # API request
  print(errors)
  assert errors == []

add_items_to_bigquery('Test1', 'some description')

def fetch_items_from_bigquery():
  bigquery_client = bigquery.Client()

  query = (
    '''
      WITH MyTable AS (
        SELECT
          *
        FROM
          `{}.{}.{}`
      )
      SELECT TO_JSON_STRING(t) AS json
      FROM MyTable AS t;
    '''
    .format('memento-mori-universitas', 'universitas_library', 'projects'))

  try:
      query_job = bigquery_client.query(query)
      data = query_job.result()
      print(data)
      # is_exist = len(data) >= 1
      print('Data exists')
      return data
  except Exception as e:
      print("Error")
      print(e)

  return False

fetch_items_from_bigquery()