done_status=['BAD_PU','TO_WH','RCVDPORT','RCVD','BAD_DEL','MISSFLT','OFFLOAD']shipments=db.db_shipment.aggregate([{"$lookup":{"from":"db_shipment_status_history","localField":"_id","foreignField":"fk_shipment_id","as":"shipment_status_history_collection"}},{"$unwind":"$shipment_status_history_co
首先要提到的是，我对Node.Js和MongoDB完全陌生。我正在使用Node.Js和MongoDB编写后端API，它将处理来自前端的GET、POST、DELETE请求，这些非常简单。我在使用DELETE功能时卡住了。这是我的posts.service.ts文件，其中包含此deletePost()函数，该函数将postId发送到后端app.js文件。`deletePost(postId:string){this.http.delete('http://localhost:3000/api/posts/'+postId).subscribe(()=>{console.log(postId
如果没有传递查询参数，我将尝试从我的Mongo集合中返回所有文档。目前我有3个可选的查询参数可以由用户传递。localhost:3000/api/projects//shouldreturnallprojects.Currentlythisisreturning[]localhost:3000/api/projects?id=1//shouldreturnprojectswithidof"1".Workingproperly.localhost:3000/api/projects?name=myproject//shouldreturnprojectswithnameof"myproj
我正在尝试对来自mongoDB集合(使用nodeJS驱动程序)的多个字段中的数组中的唯一值进行排序。一个小数据集:[{"_id":"5c93db3dd0184516406013f7","filters":{"genres":[{"_id":"9CXBYc4qP8sqcNMZ5","fr":"ArtAbstrait","en":"AbstractArt","de":"AbstrakteKunst","it":"Arteastratta","es":"ArteAbstracto"}],"subjects":[{"_id":"3QjL6YSfmuY6NFHGG","fr":"Abstrait
我正在编写一个使用MongoRepository实现查询的方法，我在Java/Spring项目中使用聚合，但在我测试时它给出了超出的内存限制。我试过newAggregationOptions().cursorBatchSize(pageable.getPageSize()).allowDiskUse(true).build()但没用我的方法:...varmatchCriteria=match(criteria);varunwindVariations=unwind("variations",false);varsort=sort(Sort.Direction.ASC,"variatio
我目前正在尝试对存储在MongoDB中的一些文档进行简单的mapreduce。我用map=BSON::Code.new"function(){emit(this.userid,1);}"用于映射和reduce=BSON::Code.new"function(key,values){varsum=0;values.forEach(function(value){sum+=value;});returnsum;}"为减少。当我按以下方式调用map_reduce时，效果很好:output=col.map_reduce(map,reduce,#colisthecollectioninmongo
我有一个包含以下内容的MongoDB集合:>db.foo.find(){"_id":1,"name":"alpha","stamp":ISODate("2013-06-13T12:12:51.111Z")}{"_id":2,"name":"bravo","stamp":ISODate("2013-06-13T12:12:52.222Z")}{"_id":3,"name":"charlie","stamp":ISODate("2013-06-13T12:12:53.333Z")}{"_id":4,"name":"delta","stamp":ISODate("2013-06-13T12:
我是mongodb的新手，我正在通过引用尝试排序选项:http://mongodb.github.io/node-mongodb-native/markdown-docs/queries.html#sorting我的代码:MongoClient.connect('mongodb://127.0.0.1/test',function(err,db){//connecttomongodbvarcollection=db.collection('qr');varoptions={"limit":20,"sort":"CARDNO"}collection.find({},options).to
我找到了thisarticleinSpringForum这显然部分讨论了相同的问题，但没有回答我的问题。给定以下文档...{"_id":{"$oid":"5214b5d529ee12460939e2ba"},"title":"thisismytitle","tags":["fun","sport"],"comments":[{"author":"alex","text":"thisiscool","createdAt":1},{"author":"sam","text":"thisisbad","createdAt":2},{"author":"jenny","text":"thisi
我对MongoDB还很陌生，尽管我无法找到对所见内容的解释。当我运行以下查询时，我有一个大约200个文档的小数据集:db.tweets.find({user:22438186})我在得到n/nscannedObjects/nscanned/nscannedObjectsAllPlans/nscannedAllPlans9.光标是BtreeCursoruser_1。都好。介绍Sort()如果我在查询中附加一个排序:db.tweets.find({user:22438186}).sort({created_at:1})nscannedObjectsAllPlans/nscannedAllP
