Query a table

Query a table with customer-managed encryption keys.

Explore further

For detailed documentation that includes this code sample, see the following:

• Customer-managed Cloud KMS keys

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.

To authenticate to BigQuery, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/bigquery"
	"google.golang.org/api/iterator"
)

// queryWithDestinationCMEK demonstrates saving query results to a destination table and protecting those results
// by specifying a customer managed encryption key.
func queryWithDestinationCMEK(w io.Writer, projectID, dstDatasetID, dstTableID 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: %w", err)
	}
	defer client.Close()

	q := client.Query("SELECT 17 as my_col")
	q.Location = "US" // Location must match the dataset(s) referenced in query.
	q.QueryConfig.Dst = client.Dataset(dstDatasetID).Table(dstTableID)
	q.DestinationEncryptionConfig = &bigquery.EncryptionConfig{
		// TODO: Replace this key with a key you have created in Cloud KMS.
		KMSKeyName: "projects/cloud-samples-tests/locations/us-central1/keyRings/test/cryptoKeys/test",
	}
	// Run the query and process the returned row iterator.
	it, err := q.Read(ctx)
	if err != nil {
		return fmt.Errorf("query.Read(): %w", err)
	}
	for {
		var row []bigquery.Value
		err := it.Next(&row)
		if err == iterator.Done {
			break
		}
		if err != nil {
			return err
		}
		fmt.Fprintln(w, row)
	}
	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.

To authenticate to BigQuery, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

import com.google.cloud.bigquery.BigQuery;
import com.google.cloud.bigquery.BigQueryException;
import com.google.cloud.bigquery.BigQueryOptions;
import com.google.cloud.bigquery.EncryptionConfiguration;
import com.google.cloud.bigquery.QueryJobConfiguration;
import com.google.cloud.bigquery.TableResult;

// Sample to query on destination table with encryption key
public class QueryDestinationTableCmek {

  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";
    String kmsKeyName = "MY_KMS_KEY_NAME";
    String query =
        String.format("SELECT stringField, booleanField FROM %s.%s", datasetName, tableName);
    EncryptionConfiguration encryption =
        EncryptionConfiguration.newBuilder().setKmsKeyName(kmsKeyName).build();
    queryDestinationTableCmek(query, encryption);
  }

  public static void queryDestinationTableCmek(String query, EncryptionConfiguration encryption) {
    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();

      QueryJobConfiguration config =
          QueryJobConfiguration.newBuilder(query)
              // Set the encryption key to use for the destination.
              .setDestinationEncryptionConfiguration(encryption)
              .build();

      TableResult results = bigquery.query(config);

      results
          .iterateAll()
          .forEach(row -> row.forEach(val -> System.out.printf("%s,", val.toString())));
      System.out.println("Query performed successfully with encryption key.");
    } catch (BigQueryException | InterruptedException e) {
      System.out.println("Query not performed \n" + e.toString());
    }
  }
}

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.

To authenticate to BigQuery, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

from google.cloud import bigquery

# Construct a BigQuery client object.
client = bigquery.Client()

# TODO(developer): Set table_id to the ID of the destination table.
# table_id = "your-project.your_dataset.your_table_name"

# Set the encryption key to use for the destination.
# TODO(developer): Replace this key with a key you have created in KMS.
# kms_key_name = "projects/{}/locations/{}/keyRings/{}/cryptoKeys/{}".format(
#     your-project, location, your-ring, your-key
# )

job_config = bigquery.QueryJobConfig(
    destination=table_id,
    destination_encryption_configuration=bigquery.EncryptionConfiguration(
        kms_key_name=kms_key_name
    ),
)

# Start the query, passing in the extra configuration.
query_job = client.query(
    "SELECT 17 AS my_col;", job_config=job_config
)  # Make an API request.
query_job.result()  # Wait for the job to complete.

table = client.get_table(table_id)  # Make an API request.
if table.encryption_configuration.kms_key_name == kms_key_name:
    print("The destination table is written using the encryption configuration")

What's next

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