rails db neutral pivot table or crosstab

Question

Does anyone know of a way to build a pivot table using activerecord which would be remotely DB neutral? I've tried to avoid using find_by_sql and DB specific queries but for a pivot table or crosstab query I have no idea how to do it in a way which is not specific to say MySQL. IE my mySQL find_by_sql breaks on a postgresql DB.

I found http://crosstab.rubyforge.org/ this obscure crosstab gem which might work, but I'm wondering if anyone else has a better solution.

Example something rediculous like this which basically just flips the axis on a table:

SELECT availables.name, rooms.id,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 0, availables.price, '')) AS day1,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 1, availables.price, '')) AS day2,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 2, availables.price, '')) AS day3,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 3, availables.price, '')) AS day4,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 4, availables.price, '')) AS day5,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 5, availables.price, '')) AS day6,
  MAX(IF(to_days(availables.bookdate) - to_days('2009-06-13') = 6, availables.price, '')) AS day7,
AVG(availables.price),SUM(availables.price)
FROM `availables`
INNER JOIN rooms
ON availables.room_id=rooms.id
WHERE availables.room_id = '18382'
GROUP BY availables.name

Answer 1

Here's a plugin that is old but might be useful: ActiveWarehouse