How can I create a time-spent-on-tasks report for a tree of tasks or single page of tasks?

Welcome. What you are asking for is hard to do with Logseq’s queries, but it seems doable one way or another.

  • Asking here is easy. But for actual help, should provide something tangible to talk about.
  • Since you are used in breaking tasks into subtasks, should do the same with this query:
    • Break it into smaller steps and try to solve each one of them separately.
    • Rather than asking for the whole query, ask for help with the individual steps.
    • Each one of those steps could be a relatively uncomplicated query.
    • When all those queries actually work, should combine them into a single complicated one.