[SERVER-32721] Explain output should indicate when a backup plan is used Created: 16/Jan/18 Updated: 06/Dec/22 |
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| Status: | Backlog |
| Project: | Core Server |
| Component/s: | Querying |
| Affects Version/s: | None |
| Fix Version/s: | None |
| Type: | Improvement | Priority: | Major - P3 |
| Reporter: | Nicholas Zolnierz | Assignee: | Backlog - Query Execution |
| Resolution: | Unresolved | Votes: | 1 |
| Labels: | neweng | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
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| Assigned Teams: |
Query Execution
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| Participants: | |||||
| Case: | (copied to CRM) | ||||
| Description |
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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. |