Learn R Programming

RMongo (version 0.0.25)

RMongo-package: MongoDB client for R.

Description

The functions in this package allow you make queries with a MongoDB database from R.

Arguments

Overview

A typical workflow using RMongo:
  1. Connect to a mongodb database:
            mongo <- mongoDbConnect("test", "localhost", 27017)  
          
  2. Insert a document into a collection: This will insert a document of '"foo":"bar"' into the "test_data" collection.
            output <- dbInsertDocument(mongo, "test_data", '{"foo": "bar"}')
          
  3. Query a MongoDB collection: This will query for documents which have a "foo" attribute with the value of "bar". The return value will be a list of rjson objects or a converted data.frame depending on the format parameter. NOTE: nested documents and arrays may not work properly if you specify a data.frame.
            output <- dbGetQuery(mongo, "test_data", 
                                        '{"foo": "bar"}')
          
    or if you want only a particular set of keys:
            output <- dbGetQueryForKeys(mongo, "test_data", 
                                        '{"foo": "bar"}', '{"foo": 1}')
          
  4. Close the connection:
            dbDisconnect(mongo)
          
  5. Large result sets: Set your java heap space to a large number to support loading more results into memory.
            options( java.parameters = "-Xmx2g" )