def METHOD_NAME(full_table_path, project_id=None, num_samples=None):
  """Read data from BigQuery and split into train and validation sets.
  Args:
    full_table_path: (string) full path of the table containing training data
      in the format of [project_id.dataset_name.table_name].
    project_id: (string, Optional) Google BigQuery Account project ID.
    num_samples: (int, Optional) Number of data samples to read.
  Returns:
    pandas.DataFrame
  """
  query = metadata.BASE_QUERY.format(table=full_table_path)
  limit = ' LIMIT {}'.format(num_samples) if num_samples else ''
  query += limit
  # Use "application default credentials"
  # Use SQL syntax dialect
  data_df = pd.read_gbq(query, project_id=project_id, dialect='standard')
  return data_df