[SERVER-84366] Incorrect selectivity in explain for complex physical plans Created: 21/Dec/23 Updated: 22/Dec/23 |
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| Status: | Backlog |
| Project: | Core Server |
| Component/s: | None |
| Affects Version/s: | None |
| Fix Version/s: | None |
| Type: | Task | Priority: | Major - P3 |
| Reporter: | Timour Katchaounov | Assignee: | Backlog - Query Optimization |
| Resolution: | Unresolved | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
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| Assigned Teams: |
Query Optimization
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| Description |
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The implementation of The selectivities of both physical nodes computed during their creation are correct, however the infrastructure in the optimizer that is supposed to pass this information to explain is not designed to do this correctly. The result is that explain shows the same CE for the PhysicalScanNode as the one of the FilterNode. Apparently explain picks the selectivity for the whole group instead of the specific per-node selectivity. As david.percy@mongodb.com said:
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