dbAggregate-methods: Performing a MongoDB aggregate query

In RMongo: MongoDB Client for R

Description

Send a set of aggregate pipeline commands to mongodb. The output is a data.frame object and will work properly only if the mongoDB collection contains primitive data types. It may not work properly if there are any embedded documents or arrays.

Usage

  dbAggregate(rmongo.object, collection, query) 

Arguments

rmongo.object	The RMongo object.
collection	The name of the collection the query is being performed upon.
query	A vector of pipeline command in JSON format. See http://docs.mongodb.org/manual/reference/aggregation/ for more information on the MongoDB aggregation framework.

See Also

mongoDbConnect

Examples

  mongo <- mongoDbConnect("test")
  # insert two records
  dbInsertDocument(mongo, "test_data", '{"foo": "bar", "size": 5 }')
  dbInsertDocument(mongo, "test_data", '{"foo": "nl", "size": 10 }')
  output <- dbAggregate(mongo, "test_data", c(' { "$project" : { "baz" : "$foo" } } ',
                                              ' { "$group" : { "_id" : "$baz" } } ',
                                              ' { "$match" : { "_id" : "bar" } } '))
  print(output)

RMongo documentation built on May 30, 2017, 2:31 a.m.