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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2k views

Can't start mongodb in ArchLinux

I have installed mongodb using sudo pacman -S mongodb in my 32-bit arch . At first I run this sudo mkdir -p /data/db to create /data/db ,and then run $ mongod ,then I got the following message : ...
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1answer
2k views

Error “cannot connect to server” installing MongoDB on Ubuntu

I'm trying to install MongoDB on Ubuntu 10.04. I followed these installation instructions. I got the following error: Error: couldn't connect to server 127.0.0.1:27017 src/mongo/shell/mongo.js:91 ...
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3k views

What does reslen and other means in mongodb log?

database.tablebusiness query: { LongitudeLatitude: { $nearSphere: [ 106.772835, -6.186753 ], $maxDistance: 0.04498373205078301 }, Prominent: { $gte: 15 }, indexContents: { $all: [ /^aru/, /^op/ ] } } ...
2
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1answer
686 views

How to add spatial indexes through rockmongo

In rockmongo we got fields for the field name and whether we should sort by ascending or descending. How to add spatial indexes then?
2
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2answers
33 views

How to find queries that timed out in MongoDB?

Is it possible to find queries in the system.profile-Collection of a MongoDB-database that did not finish due to a timeout? I found some queries that ran longer than the time specified in $maxTimeMS. ...
2
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2answers
221 views

Why does mongodb require three config servers

The official mongodb documentation states to use three config servers. They say its for redudancy, because 1 server would be a point of failure.... but why not 2? in a production sharded cluster, if I ...
2
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1answer
166 views

Mongodb: too many namespaces raise on setProfiling

I have a mongodb database with a single (relatively big, around 130GB) collection, with 3 indexes, on which I'd like to do some profiling. However when I run the db.setProfilinStatus(1, 1000) command, ...
2
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1answer
651 views

errno 98 but no other mongod running

Here are my config options: options: { config: "/etc/mongod.conf" , net: { bindIp: "127.0.0.1, 10.0.2.57" } , processManagement: { fork: true, pidFilePath: "/var/run/mongodb/mongod.pid" } , storage: ...
2
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1answer
4k views

How to limit the connections per host in MongoDB?

I'm running a mongo server which accepts connections from other clients through java driver. The thing I have noticed is after a while some users open too many ports, and this prevents other users to ...
2
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1answer
73 views

What folders should I check to see if these MongoDB applications are installed on my server?

I have a CentOS (Linux) server and looked at the /bin directory, but don't find the applications listed below. What folders should I check to see if these applications are installed on my server? I'm ...
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2answers
138 views

Is it always faster to create indexes after loading data?

I have a large number of records (~1 billion) that I need to load into MongoDB (actually TokuMX, but whatever). I have about 6 different indices I need to create on the collection. Is it always faster ...
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501 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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1answer
964 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 ...
2
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1answer
1k views

Mongo authentication user can't drop database

my question is - is it possible to define user in the Mongo database who will be able to drop the database? Maximum user privilege is "dbAdmin" but that privilege doesn't allow users to drop the ...
2
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1answer
145 views

Riak in SasS application

I am thinking about using Riak for a SasS application I started working on recently. I was originally thinking about MongoDB but after running into Riak it seems like it may be the better option. The ...
2
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1answer
5k views

mongodb: drop all collections

How to remove existing content before entering a replicaset the first time? mongodb worries about: ... has data already, cannot initiate set. All members except initiator must be empty.
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1answer
55 views

Dynamic relations in MongoDB

I'm designing a document with MongoDB where users have relationships with each other. Easy enough, right? { _id: "012", username: "happy4u", // ... related: [ '123', // user ...
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2answers
381 views

Mongos version 3.0.1 Split Chunk Error with Sharding

I have 3 config server and two shards. Each shard has a primary, secondary and an arbiter. This is running with the following mongod settings: storageEngine=wiredTiger ...
2
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1answer
2k views

how to upgrade the config servers to use WiredTiger in mongodb 3.0.0

I am reading the document upgrade config servers to use WiredTiger. In the section of "change config server to use WiredTiger", the second step is "stop the last config server listed in the mongos' ...
2
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1answer
257 views

Do MongoDB's “read uncommit” and “write lock” conflict with each other?

I was reading the MongoDB documentation, where it says about read uncommit: MongoDB allows clients to read documents inserted or modified before it commits these modifications to disk, regardless of ...
2
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1answer
897 views

MongoDB ReplicaSet reconfig when primary and majority don't exist

http://docs.mongodb.org/manual/tutorial/reconfigure-replica-set-with-unavailable-members/ Is there anyway to reconfigure a replica set in the event the primary as well as a majority of the servers ...
2
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1answer
450 views

mongodb: maxTimeMS ignored

After trying with different drivers and clients, we suffer with mongodb timeout on find query. Even Profiling logs the settings and issue well. 2014-08-13T23:46:43.218+0200 [conn80] query ...
2
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1answer
262 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
1k 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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2answers
555 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
512 views

Should I save “document ID” as a String or Number in MongoDB

So I'm importing about a 100,000 documents into mondoDB. MongoDB already generates an Object hash but the data has a documentID that was used to identify records in the previous database. The IDs ...
2
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1answer
67 views

How to handle “or” possibilities in MongoDB

I'm new to MongoDB and by no means an expert in DB design in general. This feels like a really basic question that's probably been answered a million times, but I'm having a surprisingly hard time ...
2
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1answer
187 views

Which database to use? [closed]

Hey there. I am looking for a free to use for commercial website database that should have these design features, in the given order: Auto-Sharding (getting more free space by adding more server ...
2
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2answers
325 views

Sharded MongoDB backup solution

I am looking for a way that I can backup my 12 MongoDB shards into a single server. Disk space is not an issue but getting the backups to be on a single node would be the best. I am not sure if there ...
2
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1answer
446 views

Preserving whitespace in MongoDB values

In a simple scenario of me inserting a key-value pair, when value contains some white space, how can I preserve it? Example: > > db.bar.insert({"name":"mike "}) > > db.bar.find() { ...
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1answer
2k views

Storing dictionaries in mongo

Is there any reliable and fast database architecture that allows to store a dictionary(containing up to hundred thousand words) using mongodb?
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2answers
3k views

How to display query result in rockmongo by using execute method

I executed a command in mongo.exe > db.tablebusiness.find({"_id": "the-simmons-paradise__41.85_-87.88"}); I got results: Now I try similar command in rockmongo. If I execute ...
2
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1answer
27 views

Sizing a MongoDB shard?

I am in the process of planning a MongoDB deployment, this will be my first to production and I have a question regarding the disk size of each shard in a cluster. This cluster itself will be for ...
2
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1answer
61 views

mongorestore failure: error writing file “/var/lib/mongodb”

I want sync my server db with my local db; dump db mongodump --db [db name] copy dump folder into my local restore dump on my local mongorestore --db [db name] [dump folder path] I ...
2
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1answer
39 views

mongodb is using most of disk space for journal and not cleaning itself

I am using mongodb on production with journal enabled. I am using mongodb to store application data and also using gridfs to store images. I am using Elastic Block Storage (EBS) with 10GB for each ...
2
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1answer
178 views

Mongodb high lock percentage / slow queries

I'm working with an application using MongoDB that is getting a fairly large number of incoming requests and I've noticed that the responses are getting slower as the number of requests get higher. ...
2
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1answer
222 views

MongoDB installation Ubuntu 12.04 LTS errors

I need some help with my MongoDB installation on a clean, fresh Ubuntu 12.04 LTS server with no nonsense installed. I thought it would be a piece of cake, but I got some errors and the Ubuntu-forums ...
2
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1answer
798 views

When upgrading config servers to use WireTiger, the running config server with wiredtiger does not authenticate the existing pass and user?

In order to upgrade mongodb to 3.0.0, I am upgrading my config servers to use WireTiger. I followed the subsection of Change Config Server to Use WiredTiger. There are 18 steps. I run mongodump --port ...
2
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1answer
96 views

MongoDB - real disk usage is LOWER than dbStats.storageFile

I'm a bit surprised by what I observe in my mongo server, so I would like to know if anybody understand how this is possible. I have one collection of around 15K documents. For each of them, I store ...
2
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1answer
113 views

Mongodump on Replica Set

Running backups on a Mongo Replica set - 1 primary, 1 secondary, 1 arbitrar. Had a instance where all three stopped talking to one another and all went to secondary. I ran a backup against the the ...
2
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2answers
124 views

MongoDB replica sets and data duplication

I am new to MongoDB and trying to understand replica sets. Specifically, I am trying to understand how MongoDB would handle the following situation: A record is written to a table with a unique ...
2
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2answers
2k views

MongoDB YAML file problems on Windows

I managed to get MongoDB running as a three member replica on Windows 8, but I had problems with configuration files. If I used the new (MongoDB 2.6) file format (YAML) and used the replica set name ...
2
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1answer
1k views

MongoDB - Query elemMatch Date

Having a document structure like this: { "_id" : ObjectId("5359816b036493327d7cae95"), "_class" : "com.myproject.MyObjectDTO", "signals" : [ { "signalType" : "ABC", "quantity" : ...
2
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1answer
260 views

What are these files in MongoDB?

I was looking into my server and I found this: [root@host ~]# cd /var/lib/mongo/journal/ [root@host journal]# ls -lh total 3.1G -rw-------. 1 mongod mongod 1.0G Apr 7 01:18 j._0 -rw-------. 1 mongod ...
2
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1answer
751 views

SpringData MongoDB - infinite getmore on mongo logs

Doing 2 queries on MongoDB through Spring Data on around 160 000 rows, query 1 is executed in few seconds (about 20 results) but query 2 never finish. I'm getting this line over and over on mongodb ...
2
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1answer
828 views

Mongodb 2.6 Server crash and not restarting

We are using mongodb 2.6 with one Primary and 2 secondaries. One of the secondary has gone bad and not restarting. 2014-04-18T21:13:34.765+0000 [rsSync] replSet still syncing, not yet to minValid ...
2
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1answer
2k views

Can't take a write lock while out of disk space

Help me please! My C:\mongodb-win32-x86_64-2.4.6\data size is 8G. I have 95G free space of drive C. But I get this message: com.mongodb.WriteConcernException: { "serverUsed" : "/127.0.0.1:27017" ...
2
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1answer
470 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
3k 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
4k views

MongoVUE connect to mongodb with authencation failed! [closed]

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 to genbank through this role by MongoVUE, but I ...