MongoDB is a scalable, high-performance, open source, document-oriented database. It supports a large number of languages and application development platforms. Questions about programming should be asked on http://stackoverflow.com.

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Script to query MongoDB with PHP [closed]

With Code Igniter and MySQL I do: $this->database->query('select * from table'); But I don't know how to use MongoDB. Can I still use this the same way to query MongoDB? ...
2
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1answer
222 views

Can arbiterOnly replica in MongoDB become SECONDARY and what it means?

The MongoDB documentation says that when a replica is added to the set as arbiterOnly=true it will not become Primary. But can Arbiter become a secondary and what does it when it does? I have a ...
2
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1answer
68 views

How do I add a user that has read access to only ONE database?

I have two databases admin and testdb ; Added a user Alice in the test database db.addUser( { user: "Alice",pwd: "Moon1234",roles: [ "readWrite" ] } ); But when I login using the user Alice, I can ...
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1answer
276 views

How can I Automate MongoDB schema design from existing MySQL Database and Logs?

I am working on the project which will automatically generate sample MongoDB schema analyzing existing MySQL database and logs. I am looking for help regarding the below questions. Please, share your ...
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1answer
873 views

Best Approach to storing chat history?

I'm building a chat application (Yes, another one :P) and am really curious about the best way to store a chat's history(String username, String Message, Time, and possibly string channel depending on ...
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372 views

Mongodb replica set : “errmsg” : “initial sync need a member to be primary or secondary to do our initial sync”,

I started primary and two secondary (which were previously running in master-slave config) in replica set on three machines with following commands mongod --replSet rs0 Then connected on one of ...
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1answer
186 views

MongoDB text index and text search

I have a mongodb collection db.articles,it has 2 keys ,"title" and "abstract".I want to do text search on these two keys.For example, the search text is "physics",and I want all the documents whose ...
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2answers
150 views

Mongodb ubuntu - config server and shard together

I have the following services on a single shard server: sudo mongod --dbpath /data/db/ --port 31001 sudo mongod --configsvr --dbpath /data/configdb/ --port 21001 The same server is using for shard ...
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1answer
708 views

How do I (safely) kill long running operations in MongoDB?

Occasionally operations get out of control in MongoDB and might end up running for hundreds of seconds, and impact performance until they are killed or completed. When that happens, I know I have ...
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1answer
1k views

How to create an efficient, scalable, multi-tenant data layer using MongoDB? [closed]

I'm working on the architecture for my upcoming Project Mangement app (as an example) and I'm seeking clarity on how best to design the MongoDB data layer, with specific regard to multi-tenancy. The ...
2
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1answer
336 views

mongodb distinct() in an array

In my mongodb database,there is only one document below: { "_id" : ObjectId("5226efc5ccf23796f9590f67"), "count" : NumberLong(126045), "eissn" : "1466-5034", "grade" : 0.0, ...
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1answer
211 views

mongosniff is missing in mongo package

I installed mongodb-10gen version 2.4.6 in Debian. This package does not include mongosniff. How can I install a pre-built version of mongosniff in Debian ?
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47 views

About transactions on mongodb

To what extent the atomic storage of mongodb can leave your database unsafe of inserts or updates on my data? In the other words. What are the possibilities of my data not been (inserted or updated) ...
0
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1answer
111 views

Scaling out mongodb on the same storage

We are planning to have some tests to predict how mongo db operates and functions with 2 terabyte of inforamtion on a single collection. So the plan is to have 15-20 sharded machines (on the same ...
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0answers
31 views

MongoDB fall into a forever waiting after a long time insert

I have a mongodb cluster,I have a very large size of data to insert to it .But it's a pitty that the insert operation seems to fall into a pause after a day's insert operation.I tried to connect to ...
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1answer
541 views

Connect to Mongo Shell on OpenShift

I have a gear running a instance of mongoDB. I wish to connect to the mongo shell. How can I do it? I have rhc and mongoDB installed on my computer. I have RockMongo on the gear, but I cannot create ...
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1answer
39 views

MongoDB Balancer:move data inside replication set or across replication set?

After reading the document of mongodb on the balancer topic , I have two questions: 1.If I set Balancer on , will the db operation efficiency will be influenced ? 2.Still ,I cannot understand ...
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1answer
92 views

Mongo db and sharding / replica sets concept questions

I have few questions about sharding and replica sets: I am planning to write important logs to a sharded environment. about 100 million rows in a day, If I will connect to a single MONGOS process , ...
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1answer
367 views

MONGODB primary became secondary after servers restart

I had this config before restart: { "_id" : "rs0", "version" : 5, "members" : [ { "_id" : 0, "host" : "Ubuntu12041vanilla:27017" }, { ...
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1answer
272 views

mongodb memory leak or big collection?

mongo 2.4.6 x64 RAM 24 GB With normal work memory consume around 10GB. After that we started read data from db (create archive raw data) memory consuming up to 90% of all memory trough 5day. And go ...
0
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1answer
354 views

Why is Mongo stuck in STARTUP2?

I have a Mongo replica set with a few secondaries. A box, which hosts a secondary instance, crashed and lost the database. I started the secondary Mongo instance again and now it's stuck in STARTUP2 ...
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1answer
377 views

GeoNear with Mongoose

This is my mongoose schema - var userDestinationSchema = mongoose.Schema({ uid: String, update_time: Date, location:{ //<INDEXED as 2d> ...
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1answer
215 views

Why does mongodb virtual memory get so large

I have just compiled MongoDB in my linuxOS and not insert any data into DB. The virtual memory is getting very large, about 40G. ps aux|grep mongod mongodb 176574 0.0 0.0 423784 39008 ...
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1answer
160 views

Which MongoDB administration UIs offer a table view (OS X)?

The only admin UI we found that offers a table view is MongoVue, which is only available on Windows. We're on Macs with OS X. Do any exist?
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1answer
229 views

What is lock pinger in mongodb

Can somebody explain me what is lock pinger in MongoDB [LockPinger] cluster XXXXXXX:27019 pinged successfully at Wed Feb 5 04:46:01 2014 by distributed lock pinger ...
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1answer
58 views

Find unauthenticated connections to MongoDB

I have many services and users that connect to MongoDB and now I need to switch on authentication. I have created some accounts and tried to ensure most users/services are now using accounts when ...
6
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1answer
5k views

MongoDB performance vs. PostgreSQL with 5.5 million rows / documents

Can someone help me compare these queries and explain why the PostgreSQL query executes in just under 2000ms and the MongoDB aggregate query takes almost 9000ms and sometimes as high as 130K ms? ...
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1answer
1k views

MongoVUE connect to mongodb with authencation failed!

I had a mongodb ,and a database named genbank ,genbank has a user whose role is "read" and "readAnyDatabase",it is very strange that I cannot connect genbank through this role by MongoVUE ,but I can ...
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1answer
136 views

mongodb equivlant query to this sql group by

I have a collection where most documents have an ISODate column. I'm wanting to get a basic count by date for that column. In MySQL if I had a datetime column on a table, to get what I'd want I'd do ...
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0answers
153 views

Issue while restarting - mongdb

I had tried to start the mongodb service using the following command in linux machine. service mongod restart I am getting the following error Stopping mongod: ...
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0answers
88 views

show database command doesn't show databases

I've made the following configuration options logpath=D:\mongodb\log\mongo.log logappend=true dbpath=D:\data\db directoryperdb=true port=64623 # [mo]ngodb maxConns=100 objcheck=true cpu=true # ...
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1answer
30 views

Line Comment in MongoDB config file

How to mark a line comment in mongodb configuration file? cpu=true #temporary for dev env Is this the right way? There is no clue about it in their website page about setting the configuration ...
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1answer
121 views

How to find MongoDB index statistics

Is there any way we can figure out what all indexes are cached into RAM ? I want to know page related stats for individual indexes (# of hits and miss )
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2answers
1k views

How to convert SQL Server database file to MongoDB? [closed]

I have .mdf / .sdf files created in SQL Server. I want to convert them to MongoDB. How can I do this?
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0answers
86 views

Mongoose: Using limit operator with subdocs match a condition

I have a Schema like this in Mongoose: var Schema = require('mongoose').Schema; var ActivitySchema = new Schema({ is_hidden : { type: Boolean, required: true, default: false }, post : ...
0
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1answer
51 views

MongoDB replication to local hard drive

MonogDB's dynamic schema has made me thinking about replacing MySQL. I eventually want to use MongoDB as the default for all new app developments. But this project runs on only 1 dedicated server ...
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1answer
78 views

How can I find out if any cluster member is offline in mongodb cluster?

I have a mongodb cluster with 1 master machine(running mongos and config service) and 3 slave machines(used as data store).But now,I find that one of 3 machines (192.168.10.11) is down because I can ...
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1answer
38 views

Does disk errors on a mongo primary instance trigger election process?

On the MongoDB site here states that a elections occurs when primary becomes unavailable. What happens if there is a disk read/write error on the primary node? Does heartbeat check covers disk health, ...
1
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1answer
526 views

How to separate MongoDB journal

I'm trying to use NFS as db path for my MongoDB (which I read is not recommended, but a client demands it that way) and I'm having trouble separating the journal files. How would I do that? I've ...
0
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1answer
23 views

Updating Document in MongoDB without Alphabetically order

I am making one project on MongoDB and inserted some documents and now i am updating the documents by this code.. bson_init( query ); bson_append_string(query, "First", "A"); ...
1
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1answer
526 views

MongoDB Keys and casting between types

This is more of a theoretical question: Let's say I have a collection of documents, my_collection: { "_id": ObjectId("52c679ac7a23e6225b62c51f"), "date": ISODate("2014-01-06T03:48:30.737Z") ...
0
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1answer
56 views

why should use MongoDB [closed]

In which types of projects, MongoDB is the best suited? Can we use MongoDB in large applications? Why Open Source CMS and framework doesn't have support for MongoDB? How it is different than other ...
0
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3answers
823 views

MongoDB doesnt start normally?

I want to start mongo on terminal but it gives connection error like: MongoDB shell version: 2.4.5 connecting to: test Sat Jan 4 10:18:16.779 JavaScript execution failed: Error: couldn't connect to ...
2
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1answer
476 views

How does MongoDB store data in RAM?

I'm trying to sift through the remains of an event that was causing us a lot troubles. Aside from report to management about what happened, I'm trying to gain a much better understanding of how this ...
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0answers
45 views

mysql vs mongodb cache/load balancing

I have a system where users can 'like' content. There will likely be many hundreds of these likes going on at once. I'd like it to be AJAX driven so you get an immediate response. At the moment I ...
0
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0answers
27 views

Overwriting Files in MongoDB GridFS using C Driver

I am new to mongodb and read about the GridFS for storing Files but when i am storing Files in GridFS, I am facing two problems 1) When I am writing a file into GridFS using C Driver, havinge same ...
0
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1answer
83 views

High Global Lock % on Mongodb

I've just started using Mongodb v2.4.8 and the global lock % averages 80% which seems rather high to me. The CPU usage is around 120% on a 2 core, 2GB RAM, SSD VPS running Ubuntu 12.04 64bit. iotop ...
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2answers
155 views

What database should I use to create a webmail service like gmail? [closed]

I planned to use python for my frontend with django framework. But for backend, I have no idea which database I should use. Since it involves plenty of reads and writes can someone point me in the ...
2
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2answers
224 views

Can I run a mongos without any config servers?

I just want to use mongos as a tool to scale up the number of connections I can open to mongo. So can I run the mongos without any config servers? Has any one done this before?
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1answer
83 views

How to manage users and collections in MongoDB? [duplicate]

Im triying to create users in a database in mongo, I want to lock the usage of te collections for some users, I'll give an example: Lets say that I actually have a db with 3 collections: Books, ...