R:使用mongolite更新mongodb中的条目 [英] R : Updating an entry in mongodb using mongolite
问题描述
我有一个mongo数据库，其中包含要传递给某些R脚本进行分析的信息.我目前正在使用mongolite包将信息从mongo传递到R.
每个mongo条目中都有一个名为checkedByR的字段，该字段是一个二进制文件，指示该条目是否已经被R脚本分析过.具体来说，我正在通过其相应的mongo ID收集mongo条目，在条目上运行脚本，为checkedByR字段分配1，然后继续.
出于完整性考虑，我正在使用以下请求查询数据库:
library(mongolite)
mongoID <- "1234abcd1234abcd1234"
m <- mongolite::mongo(url = "mongodb://localhost:27017",
collection = "collection",
db = "database")
rawData <- m$find(query = paste0('{"_id": { "$oid" : "',mongoID,'" }}'),
fields = '{"_id" : 1,
"checkedByR" : 1,
"somethingToCheck" : 1}')
checkedByR <- 1
但是，我很难用新的checkedByR字段成功更新mongo条目.
我意识到mongolite软件包中存在update函数(请考虑: https://cran.r-project.org/web/packages/mongolite/mongolite.pdf )，但是我在收集相关示例以帮助我完成更新过程方面遇到了麻烦.
任何帮助将不胜感激.
mongo$update()函数采用query和update自变量.您使用query查找要更新的数据，并使用update告诉它要更新哪个字段.
考虑此示例
library(mongolite)
## create some dummy data and insert into mongodb
df <- data.frame(id = 1:10,
value = letters[1:10])
mongo <- mongo(collection = "another_test",
db = "test",
url = "mongodb://localhost")
mongo$insert(df)
## the 'id' of the document I want to update
mongoID <- "575556825dabbf2aea1d7cc1"
## find some data
rawData <- mongo$find(query = paste0('{"_id": { "$oid" : "',mongoID,'" }}'),
fields = '{"_id" : 1,
"id" : 1,
"value" : 1}')
## ...
## do whatever you want to do in R...
## ...
## use update to query on your ID, then 'set' to set the 'checkedByR' value to 1
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$set" : { "checkedByR" : 1} }')
## in my original data I didn't have a 'checkedByR' value, but it's added anyway
更新
rmongodb库不再位于CRAN上，因此下面的代码将不起作用
对于更复杂的结构&更新您可以执行的操作
library(mongolite)
library(jsonlite)
library(rmongodb) ## used to insert a non-data.frame into mongodb
## create some dummy data and insert into mongodb
lst <- list(id = 1,
value_doc = data.frame(id = 1:5,
value = letters[1:5],
stringsAsFactors = FALSE),
value_array = c(letters[6:10]))
## using rmongodb
mongo <- mongo.create(db = "test")
coll <- "test.another_test"
mongo.insert(mongo,
ns = coll,
b = mongo.bson.from.list(lst))
mongo.destroy(mongo)
## update document with specific ID
mongoID <- "5755f646ceeb7846c87afd90"
## using mongolite
mongo <- mongo(db = "test",
coll = "another_test",
url = "mongodb://localhost")
## to add a single value to an array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_array" : "checkedByR" } }')
## To add a document to the value_array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_array" : { "checkedByR" : 1} } }')
## To add to a nested array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_doc.value" : "checkedByR" } }')
rm(mongo); gc()
有关更多详细信息，请参见 mongodb更新文档
>I have a mongo database with information that I am passing to some R scripts for analysis. I am currently using the mongolite package to pass the information from mongo to R.
I have a field in each mongo entry called checkedByR, which is a binary that indicates whether the entry has been analysed by the R scripts already. Specifically, I am collecting a mongo entry by its respective mongo ID, running the scripts on the entry, assigning the checkedByR field with a 1, and then moving on.
For completeness, I am querying the database with the following request:
library(mongolite)
mongoID <- "1234abcd1234abcd1234"
m <- mongolite::mongo(url = "mongodb://localhost:27017",
collection = "collection",
db = "database")
rawData <- m$find(query = paste0('{"_id": { "$oid" : "',mongoID,'" }}'),
fields = '{"_id" : 1,
"checkedByR" : 1,
"somethingToCheck" : 1}')
checkedByR <- 1
However, I am having trouble successfully updating the mongo entry with the new checkedByR field.
I realise that an update function exists in the mongolite package (please consider : https://cran.r-project.org/web/packages/mongolite/mongolite.pdf), but I am having trouble gathering relevant examples to help me complete the updating process.
Any help would be greatly appreciated.
the mongo$update() function takes a query and a update argument. You use the query to find the data you want to update, and the update to tell it which field to update.
Consider this example
library(mongolite)
## create some dummy data and insert into mongodb
df <- data.frame(id = 1:10,
value = letters[1:10])
mongo <- mongo(collection = "another_test",
db = "test",
url = "mongodb://localhost")
mongo$insert(df)
## the 'id' of the document I want to update
mongoID <- "575556825dabbf2aea1d7cc1"
## find some data
rawData <- mongo$find(query = paste0('{"_id": { "$oid" : "',mongoID,'" }}'),
fields = '{"_id" : 1,
"id" : 1,
"value" : 1}')
## ...
## do whatever you want to do in R...
## ...
## use update to query on your ID, then 'set' to set the 'checkedByR' value to 1
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$set" : { "checkedByR" : 1} }')
## in my original data I didn't have a 'checkedByR' value, but it's added anyway
Update
the rmongodb library is no longer on CRAN, so the below code won't work
And for more complex structures & updates you can do things like
library(mongolite)
library(jsonlite)
library(rmongodb) ## used to insert a non-data.frame into mongodb
## create some dummy data and insert into mongodb
lst <- list(id = 1,
value_doc = data.frame(id = 1:5,
value = letters[1:5],
stringsAsFactors = FALSE),
value_array = c(letters[6:10]))
## using rmongodb
mongo <- mongo.create(db = "test")
coll <- "test.another_test"
mongo.insert(mongo,
ns = coll,
b = mongo.bson.from.list(lst))
mongo.destroy(mongo)
## update document with specific ID
mongoID <- "5755f646ceeb7846c87afd90"
## using mongolite
mongo <- mongo(db = "test",
coll = "another_test",
url = "mongodb://localhost")
## to add a single value to an array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_array" : "checkedByR" } }')
## To add a document to the value_array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_array" : { "checkedByR" : 1} } }')
## To add to a nested array
mongo$update(query = paste0('{"_id": { "$oid" : "', mongoID, '" } }'),
update = '{ "$addToSet" : { "value_doc.value" : "checkedByR" } }')
rm(mongo); gc()
see mongodb update documemtation for further details
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