I'm using the PublicActivity gem: https://github.com/pokonski/public_activity
All of the models I use PublicActivity to track use the column edition_id. And I'm wondering how I can scope by that column since it's polymorphic relation.
Eg PublicActivity looks like so:
PublicActivity::Activity.limit(50)
+----+--------------+----------------+----------+------------+--------------------+------------+--------------+----------------+---------------------------+---------------------------+
| id | trackable_id | trackable_type | owner_id | owner_type | key | parameters | recipient_id | recipient_type | created_at | updated_at |
+----+--------------+----------------+----------+------------+--------------------+------------+--------------+----------------+---------------------------+---------------------------+
| 1 | 42 | QuizMaster | 6 | User | quiz_master.update | {} | | | 2013-04-12 17:33:14 +0100 | 2013-04-12 17:33:14 +0100 |
| 2 | 25 | Place | 6 | User | place.update | {} | | | 2013-04-12 17:42:42 +0100 | 2013-04-12 17:42:42 +0100 |
| 3 | 25 | Event | 6 | User | event.update | {} | | | 2013-04-12 17:45:08 +0100 | 2013-04-12 17:45:08 +0100 |
| 4 | 20 | QuizMaster | 6 | User | quiz_master.update | {} | | | 2013-04-12 17:49:09 +0100 | 2013-04-12 17:49:09 +0100 |
| 5 | 20 | QuizMaster | 6 | User | quiz_master.update | {} | | | 2013-04-12 17:50:51 +0100 | 2013-04-12 17:50:51 +0100 |
+----+--------------+----------------+----------+------------+--------------------+------------+--------------+----------------+---------------------------+---------------------------+
Where edition_id is on the polymorphic trackable relation.
What I would like to do it something like:
PublicActivity::Activity.limit(50).includes(:trackable)# where trackable edition = 1
I'm not sure how or even if it's possible to join or include or preload a polymorphic model across multiple "trackable" types.
I don't think this is possible directly with SQL because of the polymorphism, but you could do something with ruby pretty easily.
PublicActivity::Activity.limit(50).select {|c| c.trackable.edition_id = 1 }
It won't be as efficient as a SQL query but using Rails preload it'll probably be good enough depending on the number of records you're fetching.
PublicActivity::Activity.limit(50).preload(:trackable).select {|c| c.trackable.edition_id = 1 }