Question

I’m rewriting a manual SQL query into an ActiveRecord query for use in a Rails app.

What it does it collect two groups of users from the same table: 1 who have a qualifying event (44 or 48) in the last week, and a group of users who have the same qualifying event a month ago.

This is the current query. I’m not sure how to turn this into an ActiveRecord scope:

select top 500 active_users_last_week.email 
    from (
      select distinct(email) from user_event_tracking
      where event_id in (44,48)
      and sitedb_created_date between getdate()-8 and getdate()-1
      and sitedb_name = 'XYZ'
      and email not like '[e-mail]'
      and email not like '%@other_company.com'
    ) active_users_last_week, 
    (
      select distinct(email) from user_event_tracking
      where event_id in (44,48)
      and sitedb_created_date between getdate()-60 and getdate()-30
      and sitedb_name = 'XYZ'
      and email not like '[e-mail]'
      and email not like '%@other_company.com
    ) active_users_last_month
where active_users_last_week.email = active_users_last_month.email;

Any suggestions on how to turn this into an ActiveRecord scope? I have these set as scopes already:

scope :active_events, lambda {
    where("event_id in (44,48)")
}

scope :for_property, lambda { |property| 
    where('sitedb_name = ?', property)
}

scope :last_week, lambda {
    where("sitedb_created_date between GETDATE()-8 and GETDATE()-1")
}

scope :last_month, lambda {
    where("sitedb_created_date between GETDATE()-60 and GETDATE()-30")
}

scope :no_test_users, lambda {
    where("email not like '[e-mail]' and email not like '%@other_company.com'")
}

The scopes all work individually (and with each other). The question is how to get emails that are in both Event.active_events.last_week and Event.active_events.last_month in an efficient way.

Answer 1

Try this:

Event.select(:email).where(:event_id => [44,48], sitedb_created_date => (8.days.ago..1.day.ago), :sitedb_name => 'XYZ', :email => Event.select(:email).where(:event_id => [44,48], sitedb_created_date => (60.days.ago..30.days.ago), :sitedb_name => 'XYZ').where(Event.arel_table[:email].does_not_match_all(["%company.com","%other_company.com"])))

You might need to tinker with days to adjust them to your date range, I am not 100% sure if they are inclusive or not. You might need to change 8.days.ago to 7.days.ago etc.

You also should be able to do this with your scopes:

Event.active_events.last_week.where(:email => Event.active_events.last_month.select(:email))