Using the rails 3 style how would I write the opposite of:
Foo.includes(:bar).where(:bars=>{:id=>nil})
I want to find where id is NOT nil. I tried:
Foo.includes(:bar).where(:bars=>{:id=>!nil}).to_sql
But that returns:
=> "SELECT \"foos\".* FROM \"foos\" WHERE (\"bars\".\"id\" = 1)"
That's definitely not what I need, and almost seems like a bug in ARel.
The canonical way to do this with Rails 3:
Foo.includes(:bar).where("bars.id IS NOT NULL")
ActiveRecord 4.0 and above adds where.not
so you can do this:
Foo.includes(:bar).where.not('bars.id' => nil)
Foo.includes(:bar).where.not(bars: { id: nil })
When working with scopes between tables, I prefer to leverage merge
so that I can use existing scopes more easily.
Foo.includes(:bar).merge(Bar.where.not(id: nil))
Also, since includes
does not always choose a join strategy, you should use references
here as well, otherwise you may end up with invalid SQL.
Foo.includes(:bar)
.references(:bar)
.merge(Bar.where.not(id: nil))