Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-32721

Explain output should indicate when a backup plan is used

    XMLWordPrintableJSON

Details

    • Icon: Improvement Improvement
    • Resolution: Unresolved
    • Icon: Major - P3 Major - P3
    • None
    • None
    • Querying
    • Query Execution

    Description

      During the investigation of a slow query, the query planner used different plans when running explain: "queryPlanner" vs. explain: "executionStats". The reason that this happened is because the original winning plan ran out of memory in the "executionStats" mode, and so the planner fell back to the backup plan. It would be helpful if the explain output included some indication when this happens.

      Attachments

        Activity

          People

            backlog-query-execution Backlog - Query Execution
            nicholas.zolnierz@mongodb.com Nicholas Zolnierz
            Votes:
            1 Vote for this issue
            Watchers:
            8 Start watching this issue

            Dates

              Created:
              Updated: