Lists all existing models in a dataset.

## Explore further


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

- [List models](https://docs.cloud.google.com/bigquery/docs/listing-models)

## 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"
    	"io"

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

    // listModels demonstrates iterating through the collection of ML models in a dataset
    // and printing a basic identifier of the model.
    func listModels(w io.Writer, projectID, datasetID string) error {
    	// projectID := "my-project-id"
    	// datasetID := "mydataset"
    	ctx := context.Background()

    	client, err := bigquery.NewClient(ctx, projectID)
    	if err != nil {
    		return fmt.Errorf("bigquery.NewClient: %w", err)
    	}
    	defer client.Close()

    	fmt.Fprintf(w, "Models contained in dataset %q\n", datasetID)
    	it := client.Dataset(datasetID).https://docs.cloud.google.com/go/docs/reference/cloud.google.com/go/bigquery/latest/index.html#cloud_google_com_go_bigquery_Dataset_Models(ctx)
    	for {
    		m, err := it.Next()
    		if err == iterator.Done {
    			break
    		}
    		if err != nil {
    			return err
    		}
    		fmt.Fprintf(w, "Model: %s\n", m.FullyQualifiedName())
    	}
    	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.api.gax.paging.https://docs.cloud.google.com/java/docs/reference/gax/latest/com.google.api.gax.paging.Page.html;
    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.BigQuery.html.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.ModelListOption.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.Model.html;

    public class ListModels {

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

      public static void listModels(String datasetName) {
        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();

          Page<Model> models = bigquery.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQuery.html#com_google_cloud_bigquery_BigQuery_listModels_com_google_cloud_bigquery_DatasetId_com_google_cloud_bigquery_BigQuery_ModelListOption____(datasetName, ModelListOption.pageSize(100));
          if (models == null) {
            System.out.println("Dataset does not contain any models.");
            return;
          }
          models
              .iterateAll()
              .forEach(model -> System.out.printf("Success! Model ID: %s", model.https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.ModelInfo.html#com_google_cloud_bigquery_ModelInfo_getModelId__()));
        } catch (https://docs.cloud.google.com/java/docs/reference/google-cloud-bigquery/latest/com.google.cloud.bigquery.BigQueryException.html e) {
          System.out.println("Models not listed in dataset due to error: \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

    # Construct a BigQuery client object.
    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()

    # TODO(developer): Set dataset_id to the ID of the dataset that contains
    #                  the models you are listing.
    # dataset_id = 'your-project.your_dataset'

    models = client.https://docs.cloud.google.com/python/docs/reference/bigquery/latest/google.cloud.bigquery.client.Client.html#google_cloud_bigquery_client_Client_list_models(dataset_id)  # Make an API request.

    print("Models contained in '{}':".format(dataset_id))
    for model in models:
        full_model_id = "{}.{}.{}".format(
            model.project, model.dataset_id, model.model_id
        )
        friendly_name = model.friendly_name
        print("{}: friendly_name='{}'".format(full_model_id, friendly_name))

## 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).