How do I find the .max of an attribute value among a group of different Models?
- by Angela
Hi, everyone: I am also open to just straight-up refactoring what I'm finding to be pretty repetitive, but to give a baseline of how it's working....
I have for every contact a Campaign, which has_many of three types of Models: Email, Call, and Letter.
When an Email (Call or Letter) has been executed for a specific contact, I have a Contact_Email(_or_Call_or_Letter) which belongs to both the Contact and the Model (Email_or_Call_or_Letter).
Each Contact_Email for example pairing has a :date_sent attribute. So does each Contact_Call and Contact_Letter.
How do I find the latest of all of them?
Here is the code I wrote that can find the latest Email and my finding retyping similar code for Call and Letter, but then stuck on how to do a .max on all of them:
def last_email(contact)
#get campaign the contact belongs to
@campaign = Campaign.find_by_id(contact.campaign_id)
@last_email = ContactEmail.find(:last,
:conditions => "contact_id = #{contact.id}",
:order => "date_sent DESC")
@last_call = ContactCall.find(:last,
:conditions => "contact_id = #{contact.id}",
:order => "date_sent DESC")
@last_letter = ContactLetter.find(:last,
:conditions => "contact_id = #{contact.id}",
:order => "date_sent DESC")
# how do I get the latest of all of these to display?
if @last_sent_email.nil?
return "no email sent"
else
return @last_sent_email.date_sent
end
end
Question 1: With what I have, how can I find effectively @last_event given I can find the last Email, last Call, and last Letter for every contact?
Question 2: How can I remove the repetitive code that I have to write for each Model?
