Rmongo查询函数给定错误
我正在尝试使用Rmongo库连接R中的mongodb。但查询函数给了我错误Rmongo查询函数给定错误,r,mongodb,rmongo,R,Mongodb,Rmongo,我正在尝试使用Rmongo库连接R中的mongodb。但查询函数给了我错误 > chn = mongoDbConnect("marketing_db", host = 'localhost', port = 27017) > print(dbShowCollections(chn)) character(0) > results = dbGetQuery(chn, marketing_data, {}, 0, 5) Error in dbGetQuery(chn, market
> chn = mongoDbConnect("marketing_db", host = 'localhost', port = 27017)
> print(dbShowCollections(chn))
character(0)
> results = dbGetQuery(chn, marketing_data, {}, 0, 5)
Error in dbGetQuery(chn, marketing_data, { :
object 'marketing_data' not found
> results = dbGetQuery(chn, "marketing_data", {}, 0, 5)
Error in (function (classes, fdef, mtable) :
unable to find an inherited method for function ‘dbGetQuery’ for signature ‘"RMongo", "character", "NULL", "numeric", "numeric"’
> results = dbGetQuery(chn, "marketing_data", query = {}, skip = 0, limit = 5)
Error in (function (classes, fdef, mtable) :
unable to find an inherited method for function ‘dbGetQuery’ for signature ‘"RMongo", "character", "NULL", "numeric", "numeric"’
其中,marketing_db是db,marketing_数据收集在my mongodb中
以下是mongo控制台的输出:
> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
marketing_db 0.001GB
myblogs 0.000GB
test 0.003GB
> use marketing_db
switched to db marketing_db
> show collections
marketing_data
> db.marketing_data.count()
7414
> db.marketing_data.find().pretty().limit(1)
{
"_id" : ObjectId("5b1d65c6cc6e576297462cdc"),
"custAge" : 55,
"profession" : "admin.",
"marital" : "single"
}
我正在为windows 3.4.3和MongoDB 3.6.5使用R
请帮助解决此错误。尝试将查询json作为字符串传递:
results = dbGetQuery(chn, "marketing_data", "{}", 0, 5)
在第一次尝试中,您没有在代码中设置
marketing\u data
变量。签名也不同:dbGetQuery(rmongo.object,collection,query,skip=0,limit=1000)
。查询应该是一个字符串,例如,{}
谢谢Bulat,它工作了,但我还有另一个问题,为什么在dbshowCollections(chn)函数中输出为字符(0)。为什么不显示集合名称?