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    Type:Improvement 
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    Resolution: Unresolved
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    Priority:Minor - P4 
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    Affects Version/s: None
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    Component/s: Index Maintenance
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        Query Execution
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It's confusing that the index on _id is unique but it doesn't report itself as such in getIndexes() or in system.indexes.
- is duplicated by
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                    SERVER-5893 autoIndexId:true creates a non-unique index on _id -         
- Closed
 
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                    SERVER-40880 _id index is not displayed as unique -         
- Closed
 
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- is related to
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                    SERVER-14128 Creating _id index with unique:false should result in error -         
- Closed
 
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