"id":51803, "ctx":"conn30","msg":"Slow query","attr":{"type":"command","ns":"test.test2","appName":"MongoDB Shell","command":{"find":"test2","filter":{"id":6},"lsid":{"id":{"$uuid":"f77ce42d-af82-4770-bacf-5e754f74eb6f"}},"$clusterTime":{"clusterTime":{"...
db.students.find({"age":19}).explain();{"queryPlanner":{"plannerVersion":1,"namespace":"mldn.students","indexFilterSet":false,"parsedQuery":{"age":{"$eq":19}},"winningPlan":{"stage":"FETCH","inputStage":{"stage":"IXSCAN","keyPattern":{"age":-1},"indexName":"age_-1","i...
"_id": ObjectId("58e1d2f0bb1bbc3245fa7571") "title": "MongoDB Index", "author": "liruihuan", "tags": ['Mongodb', 'Index', 'Query'], "pages": 3, "time" : ISODate("2017-04-09T11:43:39.236Z") }, { "_id": ObjectId("58e1d2f0bb1bbc3245fa7572") "title": "MongoDB ...
测试程序点击这里下载。测试基于单个master的mongodb,后续测试发现,如果开启master/slave的话,写入速度非常不稳定,在向slave传送数据的时候写入速度下降50%到80%。还有就是mongodb随着并发的上升并没有带来写入速度上的提高,反而下降了一点,可能是因为读写锁的关系。 另外,点击这里下载一个查看mongodb对象的小工具(基于...
filter: { operationType:"insert", "fullDocument.type":"perennial", }, })) { //The change eventwillalways represent anewly inserted perennial const{ documentKey, fullDocument } = change; console.log(`new document:${documentKey}`, fullDocument); ...
1.mongodb介绍 MongoDB是一种存储文档的非关系型数据库,是无模式的文档型数据库. 所谓的无模式就是第一个文档和第二个文档没有任何关系,每一个document都是独立的. 所谓的文档是一种类似于json的结构,叫BSON(binary json),BSON是一个轻量级的二进制数据格式.已
To use an operation rejection filter in the Atlas UI: 1 In Atlas, go to theClusterspage for your project. If it's not already displayed, select the organization that contains your desired project from theOrganizationsmenu in the navigation bar. ...
An array of bulkWrite operations to perform. Examples of supported operations include the following: { insertOne: { document: { a: 1 } } } { updateOne: { filter: {a:2}, update: {$set: {a:2}}, upsert:true } } { updateMany: { filter: {a:2}, update: {$set: {a:2}}, ups...
# 正确:"$all":array 中 属性amenities 包含 "Gym","Internet"两个value值的document # 顺序无关 {"amenities":{"$all":["Gym","Internet"]}} db.listingsAndReviews.find({"amenities":{"$all":["Gym","Internet"]}}).count() # 正确:$size 限制array的length ...
4. Length of Database Names 不能为空且小于64个字符 5. Restriction on Collection Names Collections必须以_或字母开头,但不能包括如下特殊字符 contain the$. be an empty string (e.g. “”). contain the null character. begin with thesystem.prefix. (Reserved for internal use.) ...