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Type:
Improvement
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Resolution: Won't Do
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Priority:
Major - P3
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None
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Affects Version/s: None
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Component/s: Index Maintenance
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Labels:
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Storage Execution
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(copied to CRM)
We should consider reporting a warning if an index build on a non-empty collection does not encounter any documents containing the key(s) specified. This can happen, for example, if there is a typo in the command. Such a warning could help mitigate performance issues and reduce the time and resources required to investigate and correct.
> db.bar.findOne()
{
"_id" : ObjectId("596e1e46970f5ca6dfaaf7d7"),
"address" : "123 Main Street"
}
>
>//It would be nice if the output of the following command indicated that the misspelled "adress" field was not found while building the index
>
> db.bar.createIndex({adress:1})
{
"createdCollectionAutomatically" : false,
"numIndexesBefore" : 1,
"numIndexesAfter" : 2,
"ok" : 1
}
>
> db.bar.find({"address" : "123 Main Street"}).explain()
{
"queryPlanner" : {
"plannerVersion" : 1,
"namespace" : "foo.bar",
"indexFilterSet" : false,
"parsedQuery" : {
"address" : {
"$eq" : "123 Main Street"
}
},
"winningPlan" : {
"stage" : "COLLSCAN",
"filter" : {
"address" : {
"$eq" : "123 Main Street"
}
},
"direction" : "forward"
},
"rejectedPlans" : [ ]
},
}