[SERVER-60638] Block $group stage from being pushed down to SBE when needsMerge is requested Created: 12/Oct/21 Updated: 29/Oct/23 Resolved: 13/Oct/21 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | None |
| Affects Version/s: | None |
| Fix Version/s: | 5.2.0 |
| Type: | Improvement | Priority: | Major - P3 |
| Reporter: | Yoon Soo Kim | Assignee: | Yoon Soo Kim |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Backwards Compatibility: | Fully Compatible |
| Sprint: | QE 2021-10-18 |
| Participants: |
| Description |
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The needsMerge behavior at mongod-side has not been yet implemented. Until it's implemented, we should block $group stage from being pushed down to SBE when needsMerge is requested from the mongos. Otherwise, it may lead to incorrect results for sharded $group, especially for accumulators that need special behavior for finalization steps when needsMerge is requested. This is just an interim fix until we implement needsMerge behavior, which is done by |