This is a sample R app, which takes two whole numbers as input and returns the sum of squares (a^2 + b^2). The code for this sample is in sum_of_squares.R. The inputs and outputs are shown below.

Inputs

Parameter	Description
`a`	The first whole number
`b`	The second whole number

Outputs

Parameter	Description
`result`	The result of calculating a^2 + b^2

Before you begin

To run this sample, you need the following prerequisites.

Software prerequisites:

SQL Server big data cluster CTP 2.3 or later.
mssqlctl. Refer to installing mssqlctl document on setting up the mssqlctl and connecting to a SQL Server 2019 big data cluster.

Run this sample

Clone or download this sample on your computer.
Log in to the SQL Server big data cluster using the command below using the IP address of the endpoint-service-proxy in your cluster. If you are not familiar with mssqltctl you can refer to the documentation and then return to this sample.
```
mssqlctl login -e https://<ip-address-of-endpoint-service-proxy>:30777 -u <user-name> -p <password>
```
Deploy the application by running the following command, specifying the folder where your spec.yaml and sum_of_squares.R files are located:
```
mssqlctl app create --spec ./sumofsq
```
Check the deployment by running the following command:
```
mssqlctl app list -n sum-of-sq -v [version]
```
Once the app is listed as Ready you can continue to the next step.

Test the app by running the following command:

mssqlctl app run -n sum-of-sq -v [version] --input a=42,b=3435

You should get output like the example below. The answer to your question are returned as result.

{
  "changedFiles": [],
  "consoleOutput": "",
  "errorMessage": "",
  "outputFiles": {},
  "outputParameters": {
    "result": 11800989.0
  },
  "success": true
}

You can clean up the sample by running the following commands:

# delete app
mssqlctl app delete --name sum-of-sq --version [version]

Sample details

Please refer to sum_of_squares.R for the code for this sample.

Spec file

Here is the spec file for this application. As you can see the sample uses the R runtime and calls the sofsq method in the sum_of_squares.R file, accepting two integer inputs named a and b and returning an integer output named result.

name: sum-of-sq
version: v1
runtime: R
src: ./sum_of_squares.R
entrypoint: sofsq
replicas: 1
poolsize: 1
inputs:
  a: integer
  b: integer
output:
  result: integer

For more information, see these articles:

How to deploy and app on SQL Server 2019 big data cluster (preview)

README.md

Running a basic R script in SQL Server big data cluster

Contents

About this sample