Update a view's query.

## Explore further


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

- [Manage logical views](https://docs.cloud.google.com/bigquery/docs/managing-views)

## Code sample

### Go


Before trying this sample, follow the Go setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Go API
reference documentation](https://godoc.org/cloud.google.com/go/bigquery).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).

    import (
    	"context"
    	"fmt"

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

    // updateView demonstrates updating the query metadata that defines a logical view.
    func updateView(projectID, datasetID, viewID string) error {
    	// projectID := "my-project-id"
    	// datasetID := "mydataset"
    	// viewID := "myview"
    	ctx := context.Background()
    	client, err := bigquery.NewClient(ctx, projectID)
    	if err != nil {
    		return fmt.Errorf("bigquery.NewClient: %w", err)
    	}
    	defer client.Close()

    	view := client.Dataset(datasetID).Table(viewID)
    	meta, err := view.Metadata(ctx)
    	if err != nil {
    		return err
    	}

    	newMeta := bigquery.https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_TableMetadataToUpdate{
    		// This example updates a view into the shakespeare dataset to exclude works named after kings.
    		ViewQuery: "SELECT word, word_count, corpus, corpus_date FROM `bigquery-public-data.samples.shakespeare` WHERE corpus NOT LIKE '%king%'",
    	}

    	if _, err := view.Update(ctx, newMeta, meta.ETag); err != nil {
    		return err
    	}
    	return nil
    }

### Java


Before trying this sample, follow the Java setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Java API
reference documentation](https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/overview).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).

    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryException.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryOptions.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.TableId.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.TableInfo.html;
    import com.google.cloud.bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.ViewDefinition.html;

    // Sample to update query on a view
    public class UpdateViewQuery {

      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 viewName = "MY_VIEW_NAME";
        String updateQuery =
            String.format("SELECT TimestampField, StringField FROM %s.%s", datasetName, tableName);
        updateViewQuery(datasetName, viewName, updateQuery);
      }

      public static void updateViewQuery(String datasetName, String viewName, String query) {
        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.
          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html bigquery = https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryOptions.html.getDefaultInstance().getService();

          // Retrieve existing view metadata
          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.TableInfo.html viewMetadata = bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_getTable_com_google_cloud_bigquery_TableId_com_google_cloud_bigquery_BigQuery_TableOption____(TableId.of(datasetName, viewName));

          // Update view query
          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.ViewDefinition.html viewDefinition = viewMetadata.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.TableInfo.html#com_google_cloud_bigquery_TableInfo__T_getDefinition__();
          https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.ViewDefinition.html updatedViewDefinition = viewDefinition.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.ViewDefinition.html#com_google_cloud_bigquery_ViewDefinition_toBuilder__().setQuery(query).build();

          // Set metadata
          bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_update_com_google_cloud_bigquery_DatasetInfo_com_google_cloud_bigquery_BigQuery_DatasetOption____(viewMetadata.toBuilder().setDefinition(https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_update_com_google_cloud_bigquery_DatasetInfo_com_google_cloud_bigquery_BigQuery_DatasetOption____dViewDefinition).build());

          System.out.println("View query updated successfully");
        } catch (https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryException.html e) {
          System.out.println("View query was not updated. \n" + e.toString());
        }
      }
    }

### Python


Before trying this sample, follow the Python setup instructions in the
[BigQuery quickstart using
client libraries](https://docs.cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries).


For more information, see the
[BigQuery Python API
reference documentation](https://docs.cloud.google.com/python/docs/reference/bigquery/latest).


To authenticate to BigQuery, set up Application Default Credentials.
For more information, see

[Set up authentication for client libraries](https://docs.cloud.google.com/bigquery/docs/authentication#client-libs).

    from google.cloud import https://docs.cloud.google.com/python/docs/reference/bigquery/latest

    client = https://docs.cloud.google.com/python/docs/reference/bigquery/latest.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html()

    view_id = "my-project.my_dataset.my_view"
    source_id = "my-project.my_dataset.my_table"
    view = https://docs.cloud.google.com/python/docs/reference/bigquery/latest.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.table.Table.html(view_id)

    # The source table in this example is created from a CSV file in Google
    # Cloud Storage located at
    # `gs://cloud-samples-data/bigquery/us-states/us-states.csv`. It contains
    # 50 US states, while the view returns only those states with names
    # starting with the letter 'M'.
    https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.AccessEntry.html#google_cloud_bigquery_dataset_AccessEntry_view.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.table.Table.html#google_cloud_bigquery_table_Table_view_query = f"SELECT name, post_abbr FROM `{source_id}` WHERE name LIKE 'M%'"

    # Make an API request to update the query property of the view.
    view = client.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html#google_cloud_bigquery_client_Client_update_table(view, ["view_query"])
    print(f"Updated {https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.AccessEntry.html#google_cloud_bigquery_dataset_AccessEntry_view.table_type}: {str(https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.dataset.AccessEntry.html#google_cloud_bigquery_dataset_AccessEntry_view.reference)}")

## What's next


To search and filter code samples for other Google Cloud products, see the
[Google Cloud sample browser](https://docs.cloud.google.com/docs/samples?product=bigquery).