| Steps To Reproduce: |
> db.foo.ensureIndex({'$**': 1})
|
{
|
"createdCollectionAutomatically" : false,
|
"numIndexesBefore" : 1,
|
"numIndexesAfter" : 2,
|
"ok" : 1
|
}
|
> db.foo.find({a:1, b:1}).explain()
|
{
|
"queryPlanner" : {
|
"plannerVersion" : 1,
|
"namespace" : "test.foo",
|
"indexFilterSet" : false,
|
"parsedQuery" : {
|
"$and" : [
|
{
|
"a" : {
|
"$eq" : 1
|
}
|
},
|
{
|
"b" : {
|
"$eq" : 1
|
}
|
}
|
]
|
},
|
"queryHash" : "43CAB4C5",
|
"planCacheKey" : "CEC1F6AF",
|
"winningPlan" : {
|
"stage" : "FETCH",
|
"filter" : {
|
"b" : {
|
"$eq" : 1
|
}
|
},
|
"inputStage" : {
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"$_path" : 1,
|
"a" : 1
|
},
|
"indexName" : "$**_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"$_path" : [ ],
|
"a" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"$_path" : [
|
"[\"a\", \"a\"]"
|
],
|
"a" : [
|
"[1.0, 1.0]"
|
]
|
}
|
}
|
},
|
"rejectedPlans" : [
|
{
|
"stage" : "FETCH",
|
"filter" : {
|
"a" : {
|
"$eq" : 1
|
}
|
},
|
"inputStage" : {
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"$_path" : 1,
|
"b" : 1
|
},
|
"indexName" : "$**_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"$_path" : [ ],
|
"b" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"$_path" : [
|
"[\"b\", \"b\"]"
|
],
|
"b" : [
|
"[1.0, 1.0]"
|
]
|
}
|
}
|
}
|
]
|
},
|
"serverInfo" : {
|
"host" : "silversurfer-wsl",
|
"port" : 27017,
|
"version" : "4.4.3",
|
"gitVersion" : "913d6b62acfbb344dde1b116f4161360acd8fd13"
|
},
|
"ok" : 1
|
}
|
Compare that to:
> db.foo.ensureIndex({a: 1})
|
{
|
"createdCollectionAutomatically" : true,
|
"numIndexesBefore" : 1,
|
"numIndexesAfter" : 2,
|
"ok" : 1
|
}
|
> db.foo.ensureIndex({b: 1})
|
{
|
"createdCollectionAutomatically" : false,
|
"numIndexesBefore" : 2,
|
"numIndexesAfter" : 3,
|
"ok" : 1
|
}
|
> db.foo.find({a:1, b:1}).explain()
|
{
|
"queryPlanner" : {
|
"plannerVersion" : 1,
|
"namespace" : "test.foo",
|
"indexFilterSet" : false,
|
"parsedQuery" : {
|
"$and" : [
|
{
|
"a" : {
|
"$eq" : 1
|
}
|
},
|
{
|
"b" : {
|
"$eq" : 1
|
}
|
}
|
]
|
},
|
"queryHash" : "43CAB4C5",
|
"planCacheKey" : "CEC1F6AF",
|
"winningPlan" : {
|
"stage" : "FETCH",
|
"filter" : {
|
"b" : {
|
"$eq" : 1
|
}
|
},
|
"inputStage" : {
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"a" : 1
|
},
|
"indexName" : "a_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"a" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"a" : [
|
"[1.0, 1.0]"
|
]
|
}
|
}
|
},
|
"rejectedPlans" : [
|
{
|
"stage" : "FETCH",
|
"filter" : {
|
"a" : {
|
"$eq" : 1
|
}
|
},
|
"inputStage" : {
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"b" : 1
|
},
|
"indexName" : "b_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"b" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"b" : [
|
"[1.0, 1.0]"
|
]
|
}
|
}
|
},
|
{
|
"stage" : "FETCH",
|
"filter" : {
|
"$and" : [
|
{
|
"a" : {
|
"$eq" : 1
|
}
|
},
|
{
|
"b" : {
|
"$eq" : 1
|
}
|
}
|
]
|
},
|
"inputStage" : {
|
"stage" : "AND_SORTED",
|
"inputStages" : [
|
{
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"a" : 1
|
},
|
"indexName" : "a_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"a" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"a" : [
|
"[1.0, 1.0]"
|
]
|
}
|
},
|
{
|
"stage" : "IXSCAN",
|
"keyPattern" : {
|
"b" : 1
|
},
|
"indexName" : "b_1",
|
"isMultiKey" : false,
|
"multiKeyPaths" : {
|
"b" : [ ]
|
},
|
"isUnique" : false,
|
"isSparse" : false,
|
"isPartial" : false,
|
"indexVersion" : 2,
|
"direction" : "forward",
|
"indexBounds" : {
|
"b" : [
|
"[1.0, 1.0]"
|
]
|
}
|
}
|
]
|
}
|
}
|
]
|
},
|
"serverInfo" : {
|
"host" : "silversurfer-wsl",
|
"port" : 27017,
|
"version" : "4.4.3",
|
"gitVersion" : "913d6b62acfbb344dde1b116f4161360acd8fd13"
|
},
|
"ok" : 1
|
}
|
|