Suppose we have two related tables, for example one representing a personERSON
name
age
...
current_status_id
and one representing a status update at a specific time for this person:STATUS_HISTORY
recorded_on
status_id
blood_pressure
length
...
I have built an application in PHP using Zend Framework, and tried to retain 'object orientedness' by using a class for representing a person and a class for representing the status of a person. I also tried to use ORM principles where possible, such as using the data mapper for separating the domain model from the data layer.What would be a nice (and object oriented) way of returning a list of persons from a data mapper, where in the list I sometimes want to know the last measured blood_pressure of the person, and sometimes not (depending on the requirements of the report/view in which the list is used). The same holds for different fields, e.g. values computed at the data layer (sum's, count's, etc.). My first thought was using a rowset (e.g. Zend_Db_Rowset) but this introduces high coupling between my view and data layer. Another way might be to return a list of persons, and then querying for each person the latest status using a data mapper for requesting the status of a specific person. However, this will result in (at least) one additional query for each person record, and does not allow me to use JOINS at the data layer.Any suggestions?
ERSON