View Source Using Fragments
Fragments allow you to use arbitrary postgres expressions in your queries. Fragments can often be an escape hatch to allow you to do things that don't have something officially supported with Ash.
Use simple expressions
fragment("? / ?", points, count)
Use entire queries
fragment("points > (SELECT SUM(points) FROM games WHERE user_id = ? AND id != ?)", user_id, id)
Using entire queries like the above is a last resort, but can often help us avoid having to add extra structure unnecessarily.