How can I clear the mongoDB oplog?

In Spring mvc + mongodb application, I have 4 lakh documents. Assuming if I need to return 3 lakh documents when a query is made, how can I do that? Following is the stack trace, HTTP Status 500 - Request processing failed; nested exception is java.lang...

Internet companies don't use AGPL licensed code. MongoDB is AGPL licensed. MongoDB Licensing 10Gen says this shouldn't be a problem since the database drivers are licensed under Apache. But if anyone else writes a custom driver, that would have to be...

Is it correct to believe that all namespaces in MongoDB - providing they encapsulate documents, can be considered collections? For example: mongodb.entities.users  {} mongodb.entities {} mongodb.content.items {} mongodb.content.comments {} This is a...

I am currently looking into an option of writing application logs to MongoDB using  log4mongo-java. Is any one logging the applications logs to mongoDB? Is it possible to run real time analysis/monitoring jobs on the log objects in MongoDB?

I have one MongoDB(version 2.0.2) instance in production environment whose resident memory keeps growing and, in about 3 months, consumes up 24G physical RAM. The memory usage stats is as below: Currently, the MongoDB instance runs well and there is...

In some data mining scenarios, I have a MongoDB collection whose records are heterogenous (i.e. they can have different keys). I often query for "which records have a field with a given key", as in db.coll.find({"fieldname":{$exists...

I read this post before putting this question : What is the best online platform for storing structured time series data and reporting on it? But have specific question to choose Cassandra or MongoDB for this, being open-source and easy licensing. I...

I have one web application written in PHP and backed by MongoDB. For each web access, there is one access log written to one MongoDB collection named access in one database visits_log. The database visits_log has only that collection to reduce write...

Hey folks, my development pc is 32 bit. and I work with mongodb. When I run the code I wrote, sometimes I get locked in MongoDB. I deleted from the file the problem solved. /var/lib/mongodb/mongod.lock So I always have to do it? Why MongoDB crashes?