json and database in r

R JSON File
JSON stands for JavaScript Object Notation. The JSON file contains the data as
text in a human-readable format. Like other files, we can also read and write
into the JSON files. For this purpose, R provides a package named rjson,
which we have to install with the help of the familiar
command install.packages.




Install rjson package
By running the following command into the R console, we will install the rjson
package into our current working directory.

1. install.packages("rjson")

Output

, Creating a JSON file
The extension of JSON file is .json. To create the JSON file, we will save the
following data as employee_info.json. We can write the information of
employees in any text editor with its appropriate rule of writing the JSON file.
In JSON files, the information contains in between the curly braces({}).

Example: employee_info.json

1. {
2. "id":["1","2","3","4","5","6","7","8" ],
3. "name":
["Shubham","Nishka","Gunjan","Sumit","Arpita","Vaishali","Anisha","Ginni" ],
4. "salary":["623","552","669","825","762","882","783","964"],
5.

, 6. "start_date":[ "1/1/2012","9/15/2013","11/23/2013","5/11/2014","3/27/201
5","5/21/2013",
7. "7/30/2013","6/17/2014"],
8. "dept":[ "IT","Operations","Finance","HR","Finance","IT","Operations","Fina
nce"]
9. }

Output




Read the JSON file
Reading the JSON file in R is a very easy and effective process. R provide
from JSON() function to extract data from a JSON file. This function, by
default, extracts the data in the form of a list. This function takes the JSON
file and returns the records which are contained in it.

Let's see an example to understand how fromJSON() function is used to
extract data and print the result in the form of a list. We will consider the
employee_info.json file which we have created before.

Example

1. # Loading the package which is required to read JSON files.
2. library("rjson")