query R from neo4j

Question

Tried to connect to neo4j from R

Ran this:

install.packages('RCurl')
install.packages('RJSONIO')
library('bitops')
library('RCurl')
library('RJSONIO')
query <- function(querystring) {
  h = basicTextGatherer()
  curlPerform(url="http://localhost:7474/db/data/ext/CypherPlugin/graphdb/execute_query",
          postfields=paste('query',curlEscape(querystring), sep='='),
          writefunction = h$update,
          verbose = FALSE
  )

  result <- fromJSON(h$value())

  data <- data.frame(t(sapply(result$data, unlist)))
  names(data) <- result.json$columns
  data
}

Then I am running:

q<-"MATCH (p:Person) RETURN p.name"
data<-query(q)

But it is giving the error:

Error in query(q) : object 'result.json' not found

I have updated R studio to 0.98.501 and R is at R-3.1.0-snowleopard.pkg . Why am I getting this error? Thanks!

Answer 1

Got this to work from a fork by Mark Needham

library('RCurl')
library('RJSONIO')

query <- function(querystring) {
 h = basicTextGatherer()
 curlPerform(url="http://localhost:7474/db/data/cypher",
             postfields=paste('query',curlEscape(querystring), sep='='),
             writefunction = h$update,
             verbose = FALSE
 )

 result <- fromJSON(h$value())

 data <- data.frame(t(sapply(result$data, unlist)))
 names(data) <- result$columns

 data 

}

Then just ran:

data <- query("START n = node(*) RETURN COUNT(n) AS count")

Worked perfectly

Answer 2

Your query has a clear error:

MATCH (p:Person) RETURN a.name

You're matching a node called "p", and returning the name property on a node called "a".

Try this instead:

MATCH (p:Person) RETURN p.name