[SERVER-1012] Value-less MapReduce (distinct on steroids) Created: 13/Apr/10 Updated: 29/Aug/11 Resolved: 29/Aug/11 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | Usability |
| Affects Version/s: | None |
| Fix Version/s: | None |
| Type: | New Feature | Priority: | Minor - P4 |
| Reporter: | Mathias Stearn | Assignee: | Unassigned |
| Resolution: | Won't Fix | Votes: | 3 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Participants: |
| Description |
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I've seen a few people using map reduce just to build a distinct list. It might be more efficient if we supported a key-only MapReduce with a single-argument emit function and no reduce phase. Whatever is emitted would just be put strait into the _id field. |
| Comments |
| Comment by Eliot Horowitz (Inactive) [ 29/Aug/11 ] |
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The other things we have planned probably handle this better. |