How do you display cursor and nscanned in mongodb 3.0?

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This is the data I showed with explain.

> db.users.explain("allPlansExecution").find({username:'user101'})
 {
 "queryPlanner" : {
 "plannerVersion" : 1,
 "namespace" : "test.users",
 "indexFilterSet" : false,
 "parsedQuery" : {
 "username" : {
 "$eq" : "user101"
 }
 },
 "winningPlan" : {
 "stage" : "FETCH",
 "inputStage" : {
 "stage" : "IXSCAN",
 "keyPattern" : {
 "username" : 1
 },
 "indexName" : "username_1",
 "isMultiKey" : false,
 "direction" : "forward",
 "indexBounds" : {
 "username" : [
 "[\"user101\", \"user101\"]"
 ]
 }
 }
 },
 "rejectedPlans" : [ ]
 },
 "executionStats" : {
 "executionSuccess" : true,
 "nReturned" : 1,
 "executionTimeMillis" : 0,
 "totalKeysExamined" : 1,
 "totalDocsExamined" : 1,
 "executionStages" : {
 "stage" : "FETCH",
 "nReturned" : 1,
 "executionTimeMillisEstimate" : 0,
 "works" : 2,
 "advanced" : 1,
 "needTime" : 0,
 "needFetch" : 0,
 "saveState" : 0,
 "restoreState" : 0,
 "isEOF" : 1,
 "invalidates" : 0,
 "docsExamined" : 1,
 "alreadyHasObj" : 0,
 "inputStage" : {
 "stage" : "IXSCAN",
 "nReturned" : 1,
 "executionTimeMillisEstimate" : 0,
 "works" : 2,
 "advanced" : 1,
 "needTime" : 0,
 "needFetch" : 0,
 "saveState" : 0,
 "restoreState" : 0,
 "isEOF" : 1,
 "invalidates" : 0,
 "keyPattern" : {
 "username" : 1
 },
 "indexName" : "username_1",
 "isMultiKey" : false,
 "direction" : "forward",
 "indexBounds" : {
 "username" : [
 "[\"user101\", \"user101\"]"
 ]
 },
 "keysExamined" : 1,
 "dupsTested" : 0,
 "dupsDropped" : 0,
 "seenInvalidated" : 0,
 "matchTested" : 0
 }
 },
 "allPlansExecution" : [ ]
 },
 "serverInfo" : {
 "host" : "mongo2",
 "port" : 27017,
 "version" : "3.0.0",
 "gitVersion" : "a841fd6394365954886924a35076691b4d149168"
 },
 "ok" : 1
 }

I just checked the documents and blamed myself for not reading the results carefully. .

queryPlanner.winningPlan.inputStage.stageColumn Display Query Policy
–IXSCANIndicates that an Index query is used
–COLLSCANIndicates the use of column queries, that is, comparing the past one by one.

cursorIndex name in moved toqueryPlanner.winningPlan.inputStage.indexName

Used in 3.0executionStats.totalDocsExaminedTo display the total number of documents to be checked and replace them.nscanned.

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