# ruby

I Had No Idea Rails Could Query the Database in Parallel

Rails can run independent database queries in parallel with `load_async` and the `async_*` aggregation helpers, turning a sequential stack of dashboard queries into concurrent ones. This post covers what it does, the thread-pool and connection-pool configuration it needs, and when *not* to reach for it. Basically: "I thought Rails ran my queries one at a time — turns out it'll run them all at once if you ask."