Query per event slows down page load

[Jwashton]

I have one timeline imported from Twitter, 2642 tweets from one user in the last year. When I try to select the timeline, or refresh the page with it already selected, I get a 6.5 second wait. Looking at the server log, I see one query being made for each event, like so:

SELECT "timelines".* FROM "timelines" INNER JOIN "events_timelines" ON "timelines"."id" = "events_timelines"."timeline_id" WHERE "events_timelines"."event_id" = $1  [["event_id", 4771]]

Is query one that we can optimize, and is it one that we even need?

[isaachermens]

What we're seeing is the effects of serializing the .events association/collection proxy. It's currently lazily-loaded, so it must hit the database for each event. I've spent a little time looking at ways to load the collection eagerly, but they seem to cause worse problems.