建立寫入串流

建立寫入串流，將資料列附加至 BigQuery 資料表。系統會以「待處理」狀態建立串流，並可用於寫入資料。資料必須先完成並提交串流，才會顯示在表格中。

程式碼範例

Node.js

在試用這個範例之前，請先按照「使用用戶端程式庫的 BigQuery 快速入門導覽課程」中的 Node.js 設定說明操作。詳情請參閱 BigQuery Node.js API 參考說明文件。

如要向 BigQuery 進行驗證，請設定應用程式預設憑證。詳情請參閱「設定用戶端程式庫的驗證作業」。

const {
  BigQueryWriteClient,
  managedwriter,
} = require('@google-cloud/bigquery-storage');
const {status} = require('@grpc/grpc-js');

const client = new BigQueryWriteClient();

/**
 * Creates a write stream of PENDING type to a BigQuery table.
 *
 * @param {string} projectId The project ID of the table, e.g. 'my-project-id'.
 * @param {string} datasetId The dataset ID of the table, e.g. 'my_dataset'.
 * @param {string} tableId The ID of the table to create a stream for, e.g. 'my_table'.
 */
async function createWriteStream(projectId, datasetId, tableId) {
  try {
    const parent = client.tablePath(projectId, datasetId, tableId);

    // A PENDING type stream is used for batch loads. The stream is created
    // in a PENDING state and does not become visible until it is committed.
    const writeStream = {
      type: managedwriter.PendingStream,
    };

    const request = {
      parent,
      writeStream,
    };

    const [response] = await client.createWriteStream(request);

    console.log('Created write stream:');
    console.log(`  ${response.name}`);
    console.log('Stream type:');
    console.log(`  ${response.type}`);
  } catch (err) {
    if (err.code === status.NOT_FOUND) {
      console.log(
        `Table ${tableId} not found in dataset ${datasetId} in project ${projectId}. Please create the table before running the sample.`,
      );
    } else {
      console.error('Error creating write stream:', err);
    }
  }
}

Python

在試用這個範例之前，請先按照「使用用戶端程式庫的 BigQuery 快速入門導覽課程」中的 Python 設定說明操作。詳情請參閱 BigQuery Python API 參考說明文件。

如要向 BigQuery 進行驗證，請設定應用程式預設憑證。詳情請參閱「設定用戶端程式庫的驗證作業」。

from google.api_core.exceptions import NotFound
from google.cloud.bigquery_storage_v1 import BigQueryWriteClient
from google.cloud.bigquery_storage_v1.types import WriteStream

client = BigQueryWriteClient()


def create_write_stream(project_id: str, dataset_id: str, table_id: str) -> None:
    """Creates a write stream to a BigQuery table.

    A write stream is a channel that can be used to write data to a BigQuery
    table. This sample creates a 'COMMITTED' type write stream, which means
    that data written to the stream is immediately available for query.

    Args:
        project_id: The Google Cloud project ID.
        dataset_id: The BigQuery dataset ID.
        table_id: The BigQuery table ID.
    """
    parent = client.table_path(project_id, dataset_id, table_id)
    write_stream = WriteStream()

    write_stream.type_ = WriteStream.Type.COMMITTED

    try:
        created_stream = client.create_write_stream(
            parent=parent, write_stream=write_stream
        )

        print(f"Created write stream: {created_stream.name}")

    except NotFound:
        print(
            f"Parent table not found: {parent}. Please create the table before running this sample."
        )

後續步驟

如要搜尋及篩選其他 Google Cloud 產品的程式碼範例，請參閱Google Cloud 範例瀏覽工具。