MongoDB : Document-Oriented NoSQL Database

learn more… | top users | synonyms

1
vote
2answers
1k views

MongoDB - Should I separate the journal and the data to different drives?

I have seen and heard from multiple sources that it can be a good idea, performance-wise, to write your db journal and your data files to separate disks. What's the recommended way to do this (e.g. ...
1
vote
2answers
1k views

Write Locks in Mongo DB

I read somewhere that mongo db holds db level write lock, does this mean that when someone updates any collection others are not allowed to read other collection or how it works. Also when someone ...
1
vote
2answers
973 views

Mongo DB Cant Start

Evening we have had a mongodb running fine for a few weeks and all of sudden it has gone down. We are unable to start it back up as it is complaining that the "dbpath (/data/db/) does not exist" I've ...
1
vote
2answers
4k views

To find a version for your pc check with the software publisher install mongodb

I want to install MongoDb on windows 8 but when i try to run C:\mongodb\bin\mongod.exeiget this error: To find a version for your pc check with the software publisher.
1
vote
1answer
2k 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/ ] } } ...
1
vote
1answer
124 views

Where do caching servers conceptually fit in my architecture?

Given the simple well-known architecture below: Where (conceptually) does the caching server(s) sit?
1
vote
3answers
128 views

How can I enter Mongo as a superuser or reset users?

I'm was playing around with permissions and locked myself out of Mongo database. I'm pretty sure I did this by trying to explicitly add access to a database but instead I overwrote only allowing ...
1
vote
1answer
80 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 , ...
1
vote
1answer
289 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 ...
1
vote
2answers
121 views

Does mongodb support non readable file?

I have uploaded PDF/PST file in mongodb by mongofiles but by retrieving them in R(BSON) and converting it to "Character" type i didnt find the PDF/PST file,so is it possible to upload PDF file or PST ...
1
vote
1answer
228 views

Books to start with big data [closed]

I would like to start learning about the big data technologies. I work in this area in the future. Does anyone know good books to start learning about it? Hadoop, HBase. Beginner - intermediate - ...
1
vote
1answer
658 views

$nearSphere returns too many data. What am I missing? Am I wrong? Is it a bug? Does other see the same thing?

I noticed that $near and $nearSphere returns completely different data and I got suspicious. After all, when latitude is near equator it sphere distance shouldn't differ a lot from euclidean distance. ...
1
vote
1answer
415 views

mongodb: replica-set processing reads on the primary

Running a replica-set with 1 primary and 2 secondaries, I wonder why the READs are also done on the primary. Shouldn't the primary mainly do the WRITEs and the secondary can share the READ-load?! I ...
1
vote
1answer
29 views

Tuning Mongo (TokuMX) for fastest bulk reads

What options do I have for tuning MongoDB / TokuMX for reading the results of queries with large result sets? I'm currently on a single server (no sharding) with the data on an SSD drive. My queries ...
1
vote
1answer
82 views

Why MongoDB starts to split before 64MB

I'm testing the MongoDB Sharding with a Sharded Collection and a forloop to insert arround 1M documents to see how splitting and moving works. I'm surprise that after few documents MongoDB starts to ...
1
vote
1answer
59 views

Maintaining mongodb for a huge list of message “documents”?

Intro: I am working on an app right now for live messaging and it's almost complete. The database strategy is in order. So when a new message is created it is sent as an object fitting my mongoDB ...
1
vote
1answer
67 views

What synchronizes two delayed replicas, which is part of the replica set, included in sharded cluster?

Please take a look at my mongodb map at http://postimg.org/image/krzvmep4d/ What synchronizes two delayed replicas, which is part of the replica set, included in sharded cluster? How can I use my ...
1
vote
1answer
120 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 ?
1
vote
1answer
296 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") ...
1
vote
1answer
53 views

Based on what criteria voting take place in MongoDB?

Suppose a replication set R1 contains one primary, 2 secondary and one arbiter node. Voting will happen if the primery node goes down. Based on what criteria secondary members will vote to select the ...
1
vote
1answer
106 views

How would I change this relational model to fit a nosql database?

Because of things beyond my control, I have to switch from a relational database to MongoDB for the advertising platform I'm helping to build. I've got a relational schema sketched out, but I'm unsure ...
1
vote
1answer
97 views

Which database is designed for storing and incrementing values?

We're trying to build a stats server that stores visits for each document on a section for a specific date, so we need a table that has the following parameters: documentID sectionID date visits ...
1
vote
1answer
137 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 ...
1
vote
1answer
155 views

What's the fastest way to replicate data?

I have a mongodb database data on my computer. I want to upload that into amazon.com server. The bottle neck is the internet connection. One way is to zip the file and then upload it to the server. ...
1
vote
1answer
77 views

How can I automate sharding in the presence of continuous reads

I am using a pymongo in a sharded mongo environment. I have some fairly write-intensive systems, so I split the data up by time, with one database per hour, so the heavy-lifting of index-updates can ...
1
vote
2answers
70 views

How to activate load balancer in sharded MongoDB

I have a very simple MongoDB database structure. Also I have 5 shards in it (3 of them are replicasets). But we testing DB loading and it seems that load balancing doesn't currently enabled. On mongos ...
1
vote
1answer
38 views

Mongodb sharded cluster backup user issue

We're using a simple python script to backup our mongodb cluster. the script connects to each mongod instance via ssh, and performs mongodump, all without requiring user/pass ever since we started ...
1
vote
3answers
123 views

How to limit MongoDB database size

Are there any mechanisms to limit the size of a single database on MongoDB 2.6? I found some options like quota, quotaFiles and nssize but am unsure how to use them.
1
vote
1answer
224 views

Error while accessing remote mongo db

Trying to access remote mongo db. Got the following error: C:\Users\ranjj_000>mongo <SERVER_IP_HERE>:28017 MongoDB shell version: 2.6.0 connecting to: 111.93.128.60:28017/test ...
1
vote
1answer
26 views

Which version of linux OS has support for MongoDB installation?

I would like to learn how to install MongoDB in my Windows machine. Currently I have a Windows 8 64 bit OS laptop and I installed MongoDB 64 version for Windows. My question is: which version of ...
1
vote
1answer
100 views

What mongodb database layout would fit better

I'm currently writing an application using the MEAN stack, pretty much only for fun and because MEAN is "cool" at the moment. Therefore I'm thinking about the database layout. The data needed to be ...
1
vote
1answer
660 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 ...
1
vote
1answer
224 views

GeoNear with Mongoose

This is my mongoose schema - var userDestinationSchema = mongoose.Schema({ uid: String, update_time: Date, location:{ //<INDEXED as 2d> ...
1
vote
1answer
64 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, ...
1
vote
1answer
25 views

Permission error replica set

I'm having some trouble with intentionally removing a secondary from a replica set. I'm trying to simulate unexpected shutdown. My replica set consists of one primary and 2 secondaries. When I shut ...
1
vote
1answer
47 views

Shard key selection for both write scaling and query isolation?

From the mongod documentation, I know that when choosing shard keys the key should always have high cardinality, so write operations are distributed to different shards (a kind of write scaling). But ...
1
vote
1answer
148 views

Shard keys must all be ascending?

I have a collection that I've been trying to shard, but I can't get it to shard with the index that I gave it. The collection in question uses a hashed index, which I created using: ...
1
vote
1answer
58 views

MySQL geospatial query optimisation suggestions

I am new to DB Administration. Trying to sort out this query which is the heart of our application. I am searching google on similar questions, but would like an experts opinion on my particular ...
1
vote
1answer
78 views

Set replica set member host names on Secondary

I have a replica set rset1 that consists of a primary, secondary, and a backup server. I recently just changed their DNS names in Route53--the only name that didn't change was the Primary's, ...
1
vote
2answers
91 views

MongoDB scaling when working with files

I have read through the MongoDB manual about sharding and replicasets. However, I would like to know if the following can be achieved with sufficient performance (read/write): Saving 10,000,000 ...
1
vote
1answer
208 views

Need a solution to store cheaply a big MongoDB collection

We have the typical problem of Twitter's timeline tweets, or Facebook profile's news: we need to show the users only the new information (storing them in a fast db), and put all the old ones somewhere ...
1
vote
1answer
368 views

I found the normal ULimit setting for mongo db is as follows:

I found the normal ULimit setting for mongo db is as follows: -f (file size): unlimited -t (cpu time): unlimited -v (virtual memory): unlimited [1] -n (open files): 64000 -m ...
1
vote
1answer
218 views

Mongo repair database “ERROR: error: exception cloning object in local.system.replset ”

I'm trying to repair a mongo database and am running into the following error early on: Wed Jul 24 16:55:21 [initandlisten] ERROR: error: exception cloning object in local.system.replset E11000 ...
1
vote
1answer
37 views

Check and remove iteratively without an index

Without sync priority or performance requirements on the task, I need to check all documents once per day and removing some of them. The find filter is not static but can be defined within a db ...
1
vote
1answer
117 views

MongoDB service not starting on RedHat - missing 'service_uri'

I'm on a Red Hat Enterprise Linux Client release 5.4 (Tikanga) machine I created my /etc/yum.repos.d/10gen.repo like this: [10gen] name=10gen Repository ...
1
vote
1answer
252 views

monitoring mongodb and mysql replications using nagios

I have set replication for mongoDB and mySQL. Now I have to manage them using nagios. I have to write some php-script that will read server status. I am good with nagios setup. Now I want to know ...
1
vote
1answer
193 views

Is it safe to remove an entry in a “config.mongos” MongoDB collection?

There are old entries in my "config.mongos"; they reference hosts which previously had "mongos" running on them but no longer do. Can I safely remove those entries? e.g.,: # Old entries { "_id" : ...
1
vote
1answer
261 views

Would Mongo's ObjectID work well in InnoDB's clustered index?

Mongo's ObjectID is defined like this: ObjectId is a 12-byte BSON type, constructed using: a 4-byte value representing the seconds since the Unix epoch, a 3-byte machine identifier, ...
1
vote
1answer
677 views

Is it possible to upgrade MongoDB from 2.0 to 2.4 directly

We have a replica set with 2 members and one arbiter in production. 10gen documentation states that 2.0 to 2.2 is a binary-compatible “drop-in" upgrade and so it's 2.2 to 2.4. Is it safe to upgrade ...
1
vote
1answer
228 views

Structuring data in MongoDB for a to-do list type application

This is a fairly high level question as I am in the initial stages of planning this application, and am also very new to MongoDB and document-based databases in general. Disclaimer aside, I am ...