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Type:
Bug
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Resolution: Works as Designed
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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: None
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Labels:
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ALL
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Execution Team 2022-01-24
While working on SERVER-61260 I’ve noticed lookups by the time field on timeseries collections that have a collation don’t set bounds for the COLLSCAN, example:
db.weather.drop();
db.createCollection(
"weather",
{
timeseries: {
timeField: "timestamp",
metaField: "metadata",
granularity: "seconds"
},
collation: {locale: "en", strength: 2}}
}
);
db.weather.find({
"timestamp": ISODate("2021-05-18T01:00:00.000Z")
}).explain()
{
"explainVersion" : "2",
"queryPlanner" : {
"namespace" : "test.weather",
"indexFilterSet" : false,
"parsedQuery" : {
"timestamp" : {
"$eq" : ISODate("2021-05-18T01:00:00Z")
}
},
"queryHash" : "911AD713",
"planCacheKey" : "911AD713",
"maxIndexedOrSolutionsReached" : false,
"maxIndexedAndSolutionsReached" : false,
"maxScansToExplodeReached" : false,
"winningPlan" : {
"queryPlan" : {
"stage" : "COLLSCAN",
"planNodeId" : 1,
"filter" : {
"timestamp" : {
"$eq" : ISODate("2021-05-18T01:00:00Z")
}
},
"direction" : "forward"
},
"slotBasedPlan" : {
"slots" : "$$RESULT=s5 $$RID=s6 env: { s3 = Timestamp(1641804498, 4) (CLUSTER_TIME), s1 = TimeZoneDatabase(Asia/Kuching...Australia/Perth) (timeZoneDB), s2 = Nothing (SEARCH_META), s4 = 1641804499092 (NOW) }",
"stages" : "[1] filter {fillEmpty (s9, false)} \n[1] traverse s9 s8 s7 [s5, s6] {s9 || s8} {s9} \nfrom \n [1] project [s7 = getField (s5, \"timestamp\")] \n [1] scan s5 s6 none none none none [] @\"cf1687e2-56d2-4971-b19e-ec89d2391f73\" true false \nin \n [1] project [s8 = fillEmpty (s7 == 1621299600000, false)] \n [1] limit 1 \n [1] coscan \n"
}
},
"rejectedPlans" : [ ]
},
"command" : {
"find" : "weather",
"filter" : {
"timestamp" : ISODate("2021-05-18T01:00:00Z")
},
"$db" : "test"
},
"serverInfo" : {
"host" : "ip-10-122-10-220",
"port" : 27017,
"version" : "5.3.0-alpha-48-g06692bd",
"gitVersion" : "06692bdbfa912848a884c6440caab9cfb693e93c"
},
"serverParameters" : {
"internalQueryFacetBufferSizeBytes" : 104857600,
"internalQueryFacetMaxOutputDocSizeBytes" : 104857600,
"internalLookupStageIntermediateDocumentMaxSizeBytes" : 104857600,
"internalDocumentSourceGroupMaxMemoryBytes" : 104857600,
"internalQueryMaxBlockingSortMemoryUsageBytes" : 104857600,
"internalQueryProhibitBlockingMergeOnMongoS" : 0,
"internalQueryMaxAddToSetBytes" : 104857600,
"internalDocumentSourceSetWindowFieldsMaxMemoryBytes" : 104857600
},
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1641804498, 4),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1641804498, 4)
}
If there's no collation the plan sets min/max bounds for the Collscan:
{
"explainVersion" : "1",
"stages" : [
{
"$cursor" : {
"queryPlanner" : {
"namespace" : "test.system.buckets.weather",
"indexFilterSet" : false,
"parsedQuery" : {
"$and" : [
{
"_id" : {
"$lte" : ObjectId("60a31190ffffffffffffffff")
}
},
{
"_id" : {
"$gte" : ObjectId("60a303800000000000000000")
}
},
{
"control.max.timestamp" : {
"$_internalExprGte" : ISODate("2021-05-18T01:00:00Z")
}
},
{
"control.min.timestamp" : {
"$_internalExprGte" : ISODate("2021-05-18T00:00:00Z")
}
},
{
"control.max.timestamp" : {
"$_internalExprLte" : ISODate("2021-05-18T02:00:00Z")
}
},
{
"control.min.timestamp" : {
"$_internalExprLte" : ISODate("2021-05-18T01:00:00Z")
}
}
]
},
"queryHash" : "D69A8284",
"planCacheKey" : "D69A8284",
"maxIndexedOrSolutionsReached" : false,
"maxIndexedAndSolutionsReached" : false,
"maxScansToExplodeReached" : false,
"winningPlan" : {
"stage" : "COLLSCAN",
"filter" : {
"$and" : [
{
"_id" : {
"$lte" : ObjectId("60a31190ffffffffffffffff")
}
},
{
"_id" : {
"$gte" : ObjectId("60a303800000000000000000")
}
},
{
"control.max.timestamp" : {
"$_internalExprGte" : ISODate("2021-05-18T01:00:00Z")
}
},
{
"control.min.timestamp" : {
"$_internalExprGte" : ISODate("2021-05-18T00:00:00Z")
}
},
{
"control.max.timestamp" : {
"$_internalExprLte" : ISODate("2021-05-18T02:00:00Z")
}
},
{
"control.min.timestamp" : {
"$_internalExprLte" : ISODate("2021-05-18T01:00:00Z")
}
}
]
},
"direction" : "forward",
"minRecord" : ObjectId("60a303800000000000000000"),
"maxRecord" : ObjectId("60a31190ffffffffffffffff")
},
"rejectedPlans" : [ ]
}
}
},
{
"$_internalUnpackBucket" : {
"exclude" : [ ],
"timeField" : "timestamp",
"metaField" : "metadata",
"bucketMaxSpanSeconds" : 3600,
"assumeNoMixedSchemaData" : true
}
},
{
"$match" : {
"timestamp" : {
"$eq" : ISODate("2021-05-18T01:00:00Z")
}
}
}
],
"serverInfo" : {
"host" : "ip-10-122-10-220",
"port" : 27017,
"version" : "5.3.0-alpha-48-g06692bd",
"gitVersion" : "06692bdbfa912848a884c6440caab9cfb693e93c"
},
"serverParameters" : {
"internalQueryFacetBufferSizeBytes" : 104857600,
"internalQueryFacetMaxOutputDocSizeBytes" : 104857600,
"internalLookupStageIntermediateDocumentMaxSizeBytes" : 104857600,
"internalDocumentSourceGroupMaxMemoryBytes" : 104857600,
"internalQueryMaxBlockingSortMemoryUsageBytes" : 104857600,
"internalQueryProhibitBlockingMergeOnMongoS" : 0,
"internalQueryMaxAddToSetBytes" : 104857600,
"internalDocumentSourceSetWindowFieldsMaxMemoryBytes" : 104857600
},
"command" : {
"aggregate" : "system.buckets.weather",
"pipeline" : [
{
"$_internalUnpackBucket" : {
"timeField" : "timestamp",
"metaField" : "metadata",
"bucketMaxSpanSeconds" : 3600,
"assumeNoMixedSchemaData" : true
}
},
{
"$match" : {
"timestamp" : ISODate("2021-05-18T01:00:00Z")
}
}
],
"cursor" : {
},
"collation" : {
}
},
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1641804443, 4),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1641804443, 4)
}