*****************未加索引******************************************

成都創(chuàng)新互聯(lián)長期為上千客戶提供的網(wǎng)站建設(shè)服務(wù)，團隊從業(yè)經(jīng)驗10年，關(guān)注不同地域、不同群體，并針對不同對象提供差異化的產(chǎn)品和服務(wù)；打造開放共贏平臺，與合作伙伴共同營造健康的互聯(lián)網(wǎng)生態(tài)環(huán)境。為興慶企業(yè)提供專業(yè)的成都網(wǎng)站制作、成都做網(wǎng)站，興慶網(wǎng)站改版等技術(shù)服務(wù)。擁有10余年豐富建站經(jīng)驗和眾多成功案例,為您定制開發(fā)。

> var startTime = new Date();

> db.temMinlog.find({"id":0}).count();

1215

>  (new Date().getTime()-startTime.getTime())/1000

194.811s

******************加索引*****************************************

> db.temMinlog.ensureIndex({"_id":1,"id":1});

{

"createdCollectionAutomatically" : false,

"numIndexesBefore" : 1,

"numIndexesAfter" : 2,

"ok" : 1

}

******************加索引后查詢*****************************************

> var startTime = new Date();

> db.temMinlog.find({"id":0}).count();

1215

>  (new Date().getTime()-startTime.getTime())/1000

227.247s

時間范圍檢索

db.temMinlog.find({"_id":{$gte:1498703926535,$lte:1498704749897},"id":0}).explain("executionStats");

結(jié)果"executionStats" : {

"executionSuccess" : true,

"nReturned" : 52,

"executionTimeMillis" : 9506,

"totalKeysExamined" : 518000,

"totalDocsExamined" : 52,

"executionStages" : {

"stage" : "FETCH",

"nReturned" : 52,

"executionTimeMillisEstimate" : 2175,

"works" : 518001,

"advanced" : 52,

"needTime" : 517947,

"needYield" : 0,

"saveState" : 8151,

"restoreState" : 8151,

"isEOF" : 1,

"invalidates" : 0,

"docsExamined" : 52,

"alreadyHasObj" : 0,

"inputStage" : {

"stage" : "IXSCAN",

"nReturned" : 52,

"executionTimeMillisEstimate" : 2145,

模糊查詢

db.temMinlog.find({"_id":{$gte:1498703926535,$lte:1498704749897},"id":/0/}).explain("executionStats");

結(jié)果"executionStats" : {

"executionSuccess" : true,

"nReturned" : 1,

"executionTimeMillis" : 9893,

"totalKeysExamined" : 518001,

"totalDocsExamined" : 1,

"executionStages" : {

"stage" : "FETCH",

"nReturned" : 1,

"executionTimeMillisEstimate" : 2237,

"works" : 518002,

"advanced" : 1,

"needTime" : 517999,

"needYield" : 0,

"saveState" : 8151,

"restoreState" : 8151,

"isEOF" : 1,

"invalidates" : 0,

"docsExamined" : 1,

"alreadyHasObj" : 0,

"inputStage" : {

"stage" : "IXSCAN",

"filter" : {

"id" : {

"$regex" : "0"

}

},

"nReturned" : 1,

"executionTimeMillisEstimate" : 2185,

模糊count（）

> var startTime = new Date();  

> db.temMinlog.find({"_id":{$gte:1498703926535,$lte:1498704749897},"id":{$in:[1,2,3]}}).count();

156

> (new Date().getTime()-startTime.getTime())/1000  

11.232s

*************************group by 統(tǒng)計*************************************

db.temMinlog.aggregate([{$group:{_id:"$id",num_tutorial:{$sum:1}}}]);

db.temMinlog.aggregate([{$group:{_id:"$id",max_v0:{$max:"$v0"},min_v1:{$min:"$v1"},count:{$sum:1}}}],{ allowDiskUse: true });

db.temMinlog.aggregate([{$group:{_id:"$id",max_v0:{$max:"$v0"},min_v1:{$min:"$v1"},avg_v2:{$avg:"$v2"},count:{$sum:1}}}],{ allowDiskUse: true });

db.temMinlog.aggregate([{$match:{_id:{$gte:1498703926535,$lte:1498704749897}}},{$group:{_id:"$id",max_v0:{$max:"$v0"},min_v1:{$min:"$v1"},avg_v2:{$avg:"$v2"},sum_v2:{$sum:"$v2"},count:{$sum:1}}}],{ allowDiskUse: true });

結(jié)果：12.194s

db.temMinlog.aggregate([{$match:{_id:{$gte:1498703926535,$lte:1498704749897}}},{$limit:5},{$group:{_id:"$id",max_v0:{$max:"$v0"},min_v1:{$min:"$v1"},avg_v2:{$avg:"$v2"},sum_v2:{$sum:"$v2"},count:{$sum:1}}},{$sort:{_id:-1}}],{ allowDiskUse: true });

$match：匹配條件，可選

$limit：結(jié)果條數(shù)，可選

$group：聚合規(guī)則

$sort：對查詢結(jié)果排序，-1表示降序

db.temMinlog.aggregate([{$match:{_id:{$gte:1498703926535,$lte:1498704749897}}},{$group:{_id:"$id",max_v0:{$max:"$v0"},min_v1:{$min:"$v1"},avg_v2:{$avg:"$v2"},sum_v2:{$sum:"$v2"},count:{$sum:1}}},{$limit:5},{$sort:{_id:-1}}]);

結(jié)果：21.048s

當(dāng)前題目：mongo聚合查詢
文章來源：http://chinadenli.net/article40/ggjieo.html

成都網(wǎng)站建設(shè)公司_創(chuàng)新互聯(lián)，為您提供品牌網(wǎng)站制作、網(wǎng)站策劃、全網(wǎng)營銷推廣、服務(wù)器托管、外貿(mào)建站、網(wǎng)站收錄

廣告

聲明：本網(wǎng)站發(fā)布的內(nèi)容（圖片、視頻和文字）以用戶投稿、用戶轉(zhuǎn)載內(nèi)容為主，如果涉及侵權(quán)請盡快告知，我們將會在第一時間刪除。文章觀點不代表本網(wǎng)站立場，如需處理請聯(lián)系客服。電話：028-86922220；郵箱：631063699@qq.com。內(nèi)容未經(jīng)允許不得轉(zhuǎn)載，或轉(zhuǎn)載時需注明來源： 創(chuàng)新互聯(lián)