When you signed up a brand new Salesforce account, you can see lots of dummy dataset (such as Acme Inc.). If you are a Salesforce developer or administrator, you might have to delete all records prior to release the account to Salesforce users (And it is really painful job).

In this case, you can do delete such records at one time by using RForcecom.

Here is a very simple code (just 20 lines) to perform.

library("RForcecom")

username<-""
password<-""
token<-""

session<-rforcecom.login(username, paste0(password,token))

deleteAll<-function(objectName){
  df<-rforcecom.retrieve(session, objectName, c("Id"))
  deleteRecords <- function(id){
    x<-as.character(id)
    rforcecom.delete(session, objectName, id)
  }
  lapply(df$Id, deleteRecords)
}
deleteAll("Contact")
deleteAll("Opportunity")
deleteAll("Lead")
deleteAll("Account")
deleteAll("Campaign")
deleteAll("ContentDocument")