mongodb-query

问题 My application has been built utilizing MongoDB as a platform. One collection in DB has massive volume of data and have opted for apache spark to retrieve and generate analytical data through calculation. I have configured Spark Connector for MongoDB to communicate with MongoDB. I need to query MongoDB collection using pyspark and build a dataframe consisting of resultset of mongodb query. Please suggest me an appropriate solution to it. 回答1: You can load the data directly into a dataframe

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 3 days ago . Improve this question Giving these classes in C# Inbox.cs public class Inbox : TDocument { public string Name {get;set;} public List<MongoDBRef> WorkOrdersRef {get;set;} public List<InboxRule> Rules {get;set;} [BsonIgnore] public List<WorkOrder> WorkOrders {get;set;} } InboxRule.cs

问题 Considering I have search pannel that inculude multiple options like in the picture below: I'm working with mongo and create compound index on 3-4 properties with specific order. But when i run a different combinations of searches i see every time different order in execution plan (explain()). Sometime i see it on Collection scan (bad) , and sometime it fit right to the index (IXSCAN). The selective fields that should handle by mongo indexes are: (brand,Types,Status,Warehouse,Carries ,Search

问题 We have a problem of aggregation queries running long time (couple of minutes). Collection: We have a collection of 250 million documents with about 20 fields per document, The total size of the collection is 110GB. We have indexes over "our_id" and dtKey fields. Hardware: Memory: 24GB RAM (6 * 4GB DIMMS 1333 Mhz) Disk: Lvm 11TB built from 4 disks of 3TB disks: 600MB/s maximum instantaneous data transfers. 7200 RPM spindle. Average latency = 4.16ms RAID 0 CPU: 2* E5-2420 0 @ 1.90GHz Total of

问题 I use aggregation framework for group by of multiple fields as { _id:{_id:"$_id",feature_type:"$feature_type",feature_name:"$feature_name"}, features: { $push: "$features" } } it give result like {_id: {_id:1,feature_type:"Test",feature_name:"Tests"}, features:["23423","32423","2342342"] } but I want result like {_id:1,feature_type:"Test",feature_name:"Tests", features:["23423","32423","2342342"] } how can i acheve this using aggregration framework. 回答1: You need to use $replaceRoot to change

问题 I use aggregation framework for group by of multiple fields as { _id:{_id:"$_id",feature_type:"$feature_type",feature_name:"$feature_name"}, features: { $push: "$features" } } it give result like {_id: {_id:1,feature_type:"Test",feature_name:"Tests"}, features:["23423","32423","2342342"] } but I want result like {_id:1,feature_type:"Test",feature_name:"Tests", features:["23423","32423","2342342"] } how can i acheve this using aggregration framework. 回答1: You need to use $replaceRoot to change

问题 I am using MongoDB Atlas cloud(https://cloud.mongodb.com/) and Mongoose library. I tried to create multiple documents using transaction concept, but it is not working. I am not getting any error. but, it seems rollback is not working properly. app.js //*** more code here var app = express(); require('./models/db'); //*** more code here models/db.js var mongoose = require( 'mongoose' ); // Build the connection string var dbURI = 'mongodb+srv://mydb:pass@cluster0-****.mongodb.net/mydb

问题 In MongoDB can we execute below written query? db.dbaname.find(userName:"abc").aggregate([]) else is there any other way we can execute CRUD and aggregate query together. 回答1: Short answer - No you can't do this : .find(userName:"abc").aggregate([]) aggregation-pipeline is heavily used for reads which is mostly similar to .find() but capable of executing complex queries with help of it's multiple stages & many aggregation-operators . there are only two stages in aggregation $out & $merge that

问题 Assume a mobile game that is backed by a MongoDB database containing a User collection with several million documents. Now assume several dozen properties that must be associated with the user - e.g. an array of _id values of Friend documents, their username, photo, an array of _id values of Game documents, last_login date, count of in-game currency, etc, etc, etc.. My concern is whether creating and updating large, growing arrays on many millions of User documents will add any 'weight' to

问题 Tried to get records from mongodb between including two days but in my code only i am getting between two days. Example: 01-06-2020 to 08-06-2020 = getting records from 02-06-2020 to 08-06-2020(01-06-2020 missing) But i want 01-06-2020 to 08-06-2020 = need to get records from 01-06-2020 to 08-06-2020. How to get it? Mongodb Data: { _id:ObjectId("5edd1df67b272e2d4cf36f70"), pname:"Test 1", category:"Choco 1", todaydate:2020-06-01T18:30:00.000+00:00 }, { _id:ObjectId("5gdd1df67b272e2d4cf36f72")