code: function(instance, callback) {
          var self = this, instanceId;
  
          instanceId = instance instanceof rackspace.DatabaseInstance ? instance.id : instance;
  
          if (!instance) {
              throw new Error('DatabaseInstance is a required argument.');
          }
  
          var requestOptions = {
              uri: '/instances/' + instanceId,
              method: 'DELETE',
              endpoint: rackspace.Endpoints.CloudDatabases
          };
  
          self.authorizedRequest(requestOptions, function(err, res, body) {
              if (err) {
                  callback(err);
                  return;
              }
  
              callback(err, res.statusCode === 202);
          });
      }
docs: @name Client.destroyDatabaseInstance
  
  @description deletes the specified instance
  
  @param {Object|String}   instance      instance or instance id to delete
  @param {Function}        callback    handles the callback of your api call