Question

I’ve looked around and can’t see any reason why my Date.yesterday query isn’t working.

I have this in my model:

  scope :yesterday, lambda {
    where('acctstarttime = ?', Time.now - 1.day)
  }

And I’ve tried

 scope :yesterday, lambda {
   where('acctstarttime = ?', (Time.now - 1.day).strftime('%Y-%m-%d'))
 }

And…

scope :yesterday, lambda {
   where('acctstarttime = ?', Date.yesterday)
 }

I get a result like this:

 Radacct.yesterday.count
 (440.1ms)  SELECT COUNT(*) FROM `radacct` WHERE (acctstarttime like '2013-01-27 22:55:31')

(I’ve also tried Date.yesterday)

Where as using today yields:

 Radacct.today.count
 SELECT COUNT(*) FROM `radacct` WHERE (acctstarttime >= '2013-01-28')
 => 16,456

If I modify the look up as follows it works:

 Radacct.find(:all, :conditions => ["acctstarttime like ?", (Date.today-1).strftime('%Y-%m-%d')+ "%"]).count

Am I just tired or is this overly complicated? What’s the best and shortest way in Rails 3 to achieve this? It seems to get stuck with the time aspect..

Answer 1

Notice the ‘>=’ on today. The problem is that you are testing equality with yesterday, when what you really want to test is a range. Try this:

scope :yesterday, lambda {
  where(:acctstarttime => Date.yesterday.beginning_of_day..Date.yesterday.end_of_day)
}

Or

scope :yesterday, lambda {
  where('acctstarttime >= ? && acctstarttime <= ?', Date.yesterday, Date.today)
}