How to get simple ForeignKey model working? (a list of class in another class) <p>I tried to figure this out on my own :( couldn't quite get there. Pls take pity. . .</p> <p>I'm trying to represent exercise data (a start time an end time and many--an undetermined number of-- heart rates)</p> <p>this is the model I have set up:</p> <pre><code>class HeartRate(models.Model): timestamp = models.DateTimeField('Date and time recorded') heartrate = models.PositiveIntegerField(default=0) def __str__(self): return prettyDate(self.timestamp) class Exercise(models.Model): start_timestamp = models.DateTimeField('Starting time') finishing_timestamp = models.DateTimeField('Finishing time') heartrate = models.ForeignKey(HeartRate) </code></pre> <p>I know from working with the admin that it seems only one HeartRate is selected for each Exercise so maybe my approach is all wrong. How do I correctly model this? And once modeled correctly how do I query all heart rates for each (all) Exercises. I know this is a noob move but I really tried for hours getting this to work and can't quite get a handle on the documentation. Thanks in advance.</p>