Get table labels

Retrieve the labels of a table for a given table ID.

Documentation pages that include this code sample

Code Sample

Go

Before trying this sample, follow the Go setup instructions in the BigQuery Quickstart Using Client Libraries. For more information, see the BigQuery Go API reference documentation. 

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/bigquery"
)

// tableLabels demonstrates fetching metadata from a table and printing the Label metadata to an io.Writer.
func tableLabels(w io.Writer, projectID, datasetID, tableID string) error {
	// projectID := "my-project-id"
	// datasetID := "mydataset"
	// tableID := "mytable"
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, projectID)
	if err != nil {
		return fmt.Errorf("bigquery.NewClient: %v", err)
	}
	defer client.Close()

	meta, err := client.Dataset(datasetID).Table(tableID).Metadata(ctx)
	if err != nil {
		return err
	}
	fmt.Fprintf(w, "Table %s labels:\n", datasetID)
	if len(meta.Labels) == 0 {
		fmt.Fprintln(w, "Table has no labels defined.")
		return nil
	}
	for k, v := range meta.Labels {
		fmt.Fprintf(w, "\t%s:%s\n", k, v)
	}
	return nil
}

Java

Before trying this sample, follow the Java setup instructions in the BigQuery Quickstart Using Client Libraries. For more information, see the BigQuery Java API reference documentation. 

import com.google.cloud.bigquery.BigQuery;
import com.google.cloud.bigquery.BigQueryException;
import com.google.cloud.bigquery.BigQueryOptions;
import com.google.cloud.bigquery.Table;
import com.google.cloud.bigquery.TableId;

// Sample to get table labels
public class GetTableLabels {

  public static void main(String[] args) {
    // TODO(developer): Replace these variables before running the sample.
    String datasetName = "MY_DATASET_NAME";
    String tableName = "MY_TABLE_NAME";
    getTableLabels(datasetName, tableName);
  }

  public static void getTableLabels(String datasetName, String tableName) {
    try {
      // Initialize client that will be used to send requests. This client only needs to be created
      // once, and can be reused for multiple requests.
      BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService();

      // This example table starts with existing label { color: 'green' }
      Table table = bigquery.getTable(TableId.of(datasetName, tableName));
      table
          .getLabels()
          .forEach((key, value) -> System.out.println("Retrieved labels successfully"));
    } catch (BigQueryException e) {
      System.out.println("Label was not deleted. \n" + e.toString());
    }
  }
}

Node.js

Before trying this sample, follow the Node.js setup instructions in the BigQuery Quickstart Using Client Libraries. For more information, see the BigQuery Node.js API reference documentation. 

// Import the Google Cloud client library
const {BigQuery} = require('@google-cloud/bigquery');
const bigquery = new BigQuery();

async function getTableLabels() {
  // Gets labels on a dataset.

  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const datasetId = "my_dataset";
  // const tableId = "my_table";

  // Retrieve current dataset metadata.
  const table = bigquery.dataset(datasetId).table(tableId);
  const [metadata] = await table.getMetadata();
  const labels = metadata.labels;

  console.log(`${tableId} Labels:`);
  for (const [key, value] of Object.entries(labels)) {
    console.log(`${key}: ${value}`);
  }
}
getTableLabels();

Python

Before trying this sample, follow the Python setup instructions in the BigQuery Quickstart Using Client Libraries. For more information, see the BigQuery Python API reference documentation. 

# from google.cloud import bigquery
# client = bigquery.Client()
# dataset_id = 'my_dataset'
# table_id = 'my_table'

project = client.project
dataset_ref = bigquery.DatasetReference(project, dataset_id)
table_ref = dataset_ref.table(table_id)
table = client.get_table(table_ref)  # API Request

# View table labels
print("Table ID: {}".format(table_id))
print("Labels:")
if table.labels:
    for label, value in table.labels.items():
        print("\t{}: {}".format(label, value))
else:
    print("\tTable has no labels defined.")