/// <summary>Determines whether this instance can execute the specified context.</summary>
    /// <param name="context">The context.</param>
    /// <param name="parameters">The parameters.</param>
    /// <returns><c>true</c> if this instance can execute the specified context; otherwise, <c>false</c>.</returns>
    public override bool CanExecute(DataContext context, Dictionary<string, string> parameters)
    {
      var statement = context.GetPreviousStatement();
      if (statement == null)
      {
        return false;
      }

      return context.GetIterator(parameters, statement);
    }