Postgres and MySQL don't guarantee that pagination with `LIMIT` and
`OFFSET` will work if the ordering isn't unique. From the Postgres docs:
> When using `LIMIT`, it is important to use an `ORDER BY` clause that
> constrains the result rows into a unique order. Otherwise you will get
> an unpredictable subset of the query's rows
Before:
[1] pry(main)> issues = 1.upto(Issue.count).map { |i| Issue.sort('priority').page(i).per(1).map(&:id) }.flatten
[2] pry(main)> issues.count
=> 81
[3] pry(main)> issues.uniq.count
=> 42
After:
[1] pry(main)> issues = 1.upto(Issue.count).map { |i| Issue.sort('priority').page(i).per(1).map(&:id) }.flatten
[2] pry(main)> issues.count
=> 81
[3] pry(main)> issues.uniq.count
=> 81
Sean McGivern
d7a5a28c53