将 BigQuery 数据集从一个区域复制到另一个区域的一种方法是利用 Storage Data Transfer Service。它没有解决您仍然必须pay for bucket-to-bucket network traffic 的事实，但可能会节省一些将数据复制到欧盟服务器的 CPU 时间。
流程将是：
- 将所有 BigQuery 表提取到与表位于同一区域的存储桶中。 （推荐 Avro 格式以获得最佳的数据类型保真度和最快的加载速度。）
- 运行存储传输作业，将提取的文件从起始位置存储桶复制到目标位置的存储桶。
- 将所有文件加载到位于目标位置的 BigQuery 数据集中。
Python 示例：
# Copyright 2018 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import datetime
import sys
import time
import googleapiclient.discovery
from google.cloud import bigquery
import json
import pytz
PROJECT_ID = 'swast-scratch' # TODO: set this to your project name
FROM_LOCATION = 'US' # TODO: set this to the BigQuery location
FROM_DATASET = 'workflow_test_us' # TODO: set to BQ dataset name
FROM_BUCKET = 'swast-scratch-us' # TODO: set to bucket name in same location
TO_LOCATION = 'EU' # TODO: set this to the destination BigQuery location
TO_DATASET = 'workflow_test_eu' # TODO: set to destination dataset name
TO_BUCKET = 'swast-scratch-eu' # TODO: set to bucket name in destination loc
# Construct API clients.
bq_client = bigquery.Client(project=PROJECT_ID)
transfer_client = googleapiclient.discovery.build('storagetransfer', 'v1')
def extract_tables():
# Extract all tables in a dataset to a Cloud Storage bucket.
print('Extracting {}:{} to bucket {}'.format(
PROJECT_ID, FROM_DATASET, FROM_BUCKET))
tables = list(bq_client.list_tables(bq_client.dataset(FROM_DATASET)))
extract_jobs = []
for table in tables:
job_config = bigquery.ExtractJobConfig()
job_config.destination_format = bigquery.DestinationFormat.AVRO
extract_job = bq_client.extract_table(
table.reference,
['gs://{}/{}.avro'.format(FROM_BUCKET, table.table_id)],
location=FROM_LOCATION, # Available in 0.32.0 library.
job_config=job_config) # Starts the extract job.
extract_jobs.append(extract_job)
for job in extract_jobs:
job.result()
return tables
def transfer_buckets():
# Transfer files from one region to another using storage transfer service.
print('Transferring bucket {} to {}'.format(FROM_BUCKET, TO_BUCKET))
now = datetime.datetime.now(pytz.utc)
transfer_job = {
'description': '{}-{}-{}_once'.format(
PROJECT_ID, FROM_BUCKET, TO_BUCKET),
'status': 'ENABLED',
'projectId': PROJECT_ID,
'transferSpec': {
'transferOptions': {
'overwriteObjectsAlreadyExistingInSink': True,
},
'gcsDataSource': {
'bucketName': FROM_BUCKET,
},
'gcsDataSink': {
'bucketName': TO_BUCKET,
},
},
# Set start and end date to today (UTC) without a time part to start
# the job immediately.
'schedule': {
'scheduleStartDate': {
'year': now.year,
'month': now.month,
'day': now.day,
},
'scheduleEndDate': {
'year': now.year,
'month': now.month,
'day': now.day,
},
},
}
transfer_job = transfer_client.transferJobs().create(
body=transfer_job).execute()
print('Returned transferJob: {}'.format(
json.dumps(transfer_job, indent=4)))
# Find the operation created for the job.
job_filter = {
'project_id': PROJECT_ID,
'job_names': [transfer_job['name']],
}
# Wait until the operation has started.
response = {}
while ('operations' not in response) or (not response['operations']):
time.sleep(1)
response = transfer_client.transferOperations().list(
name='transferOperations', filter=json.dumps(job_filter)).execute()
operation = response['operations'][0]
print('Returned transferOperation: {}'.format(
json.dumps(operation, indent=4)))
# Wait for the transfer to complete.
print('Waiting ', end='')
while operation['metadata']['status'] == 'IN_PROGRESS':
print('.', end='')
sys.stdout.flush()
time.sleep(5)
operation = transfer_client.transferOperations().get(
name=operation['name']).execute()
print()
print('Finished transferOperation: {}'.format(
json.dumps(operation, indent=4)))
def load_tables(tables):
# Load all tables into the new dataset.
print('Loading tables from bucket {} to {}:{}'.format(
TO_BUCKET, PROJECT_ID, TO_DATASET))
load_jobs = []
for table in tables:
dest_table = bq_client.dataset(TO_DATASET).table(table.table_id)
job_config = bigquery.LoadJobConfig()
job_config.source_format = bigquery.SourceFormat.AVRO
load_job = bq_client.load_table_from_uri(
['gs://{}/{}.avro'.format(TO_BUCKET, table.table_id)],
dest_table,
location=TO_LOCATION, # Available in 0.32.0 library.
job_config=job_config) # Starts the load job.
load_jobs.append(load_job)
for job in load_jobs:
job.result()
# Actually run the script.
tables = extract_tables()
transfer_buckets()
load_tables(tables)
上述示例将 google-cloud-bigquery 库用于 BigQuery API，将 google-api-python-client 用于存储数据传输 API。
请注意，此示例不考虑分区表。