The [PostgreSQL node-postgres driver](https://node-postgres.com/) is the official Node.js driver for PostgreSQL which can be used to connect with YugabyteDB YSQL API. Because YugabyteDB YSQL API is fully compatible with PostgreSQL node-postgres (pg) driver, it allows Node.js programmers to connect to the YugabyteDB database to execute DMLs and DDLs using the node-postgres APIs.
## CRUD operations
The following sections demonstrate how to perform common tasks required for Node.js application development using the PostgreSQL node-postgres driver.
To start building your application, make sure you have met the [prerequisites](../#prerequisites).
### Step 1: Install the driver dependency and async utility
Download and install the node-postgres driver using the following command (you need to have Node.js installed on your system):
```sh
npm install pg
```
To install the async utility, run the following command:
```sh
$ npm install --save async
```
You can start using the driver in your code.
### Step 2: Set up the database connection
The following table describes the connection parameters required to connect.
| Parameter | Description | Default |
| :-------- | :---------- | :------ |
| host | Hostname of the YugabyteDB instance | localhost |
| port | Listen port for YSQL | 5433 |
| database | Database user | yugabyte |
| user | User connecting to the database | yugabyte |
| password | User password | yugabyte |
Before connecting to the YugabyteDB cluster, import the `pg` package.
```js
const pg = require('pg');
```
Create a client to connect to the cluster using a connection string.
```javascript
const connectionString = "postgresql://user:password@localhost:port/database"
const client = new Client(connectionString);
client.connect()
```
#### Use SSL
The following table describes the connection parameters required to connect using TLS/SSL.
| Parameter | Description |
| :-------- | :---------- |
| sslmode | SSL mode |
| sslrootcert | path to the root certificate on your computer |
By default, the driver supports the `require` SSL mode, in which a root CA certificate isn't required to be configured. This enables SSL communication between the Node.js client and YugabyteDB servers.
```js
const config = {
user: ' ',
database: ' ',
host: ' ',
password: ' ',
port: 5433,
// this object will be passed to the TLSSocket constructor
ssl: {
rejectUnauthorized: false,
},
}
```
If you created a cluster on YugabyteDB Aeon, use the cluster credentials and [download the SSL Root certificate](/stable/yugabyte-cloud/cloud-secure-clusters/cloud-authentication/#download-your-cluster-certificate).
Refer to [Configure SSL/TLS](../postgres-pg-reference/#configure-ssl-tls) for more information on node-postgresql default and supported SSL modes, and other examples for setting up your connection strings when using SSL.
### Step 3: Write your application
Create a new JavaScript file called `QuickStartApp.js` in your project directory.
Copy the following sample code to set up tables and query the table contents. Replace the connection string parameters with the cluster credentials if required.
```js
var pg = require('pg');
const async = require('async');
const assert = require('assert');
var connectionString = "postgres://postgres@localhost:5433/postgres";
var client = new pg.Client(connectionString);
async.series([
function connect(next) {
client.connect(next);
},
function createTable(next) {
// The create table statement.
const create_table = 'CREATE TABLE employee (id int PRIMARY KEY, ' +
'name varchar, ' +
'age int, ' +
'language varchar);';
// Create the table.
console.log('Creating table employee');
client.query(create_table, next);
},
function insert(next) {
// Create a variable with the insert statement.
const insert = "INSERT INTO employee (id, name, age, language) " +
"VALUES (1, 'John', 35, 'NodeJS');";
// Insert a row with the employee data.
console.log('Inserting row with: %s', insert)
client.query(insert, next);
},
function select(next) {
// Query the row for employee id 1 and print the results to the console.
const select = 'SELECT name, age, language FROM employee WHERE id = 1;';
client.query(select, function (err, result) {
if (err) return next(err);
var row = result.rows[0];
console.log('Query for id=1 returned: name=%s, age=%d, language=%s',
row.name, row.age, row.language);
next();
});
}
], function (err) {
if (err) {
console.error('There was an error', err.message, err.stack);
}
console.log('Shutting down');
client.end();
});
```
Run the application `QuickStartApp.js` using the following command:
```js
node QuickStartApp.js
```
You should see output similar to the following:
```output
Creating table employee
Inserting row with: INSERT INTO employee (id, name, age, language) VALUES (1, 'John', 35, 'NodeJS');
Query for id=1 returned: name=John, age=35, language=NodeJS
Shutting down
```
### Step 4: Write your application with SSL (Optional)
Copy the following sample code to QuickStartApp.js and replace the values for the `config` object as appropriate for your cluster if you're using SSL.
```js
var pg = require('pg');
const async = require('async');
const assert = require('assert');
const fs = require('fs');
const config = {
user: 'admin',
database: 'yugabyte',
host: '22420e3a-768b-43da-8dcb-xxxxxx.aws.yugabyte.cloud',
password: 'xxxxxx',
port: 5433,
// this object will be passed to the TLSSocket constructor
ssl: {
rejectUnauthorized: false,
},
}
var client = new pg.Client(config);
async.series([
function connect(next) {
client.connect(next);
},
function createTable(next) {
// The create table statement.
const create_table = 'CREATE TABLE IF NOT EXISTS employee (id int PRIMARY KEY, ' +
'name varchar, ' +
'age int, ' +
'language varchar);';
// Create the table.
console.log('Creating table employee');
client.query(create_table, next);
},
function insert(next) {
// Create a variable with the insert statement.
const insert = "INSERT INTO employee (id, name, age, language) " +
"VALUES (2, 'John', 35, 'NodeJS + SSL');";
// Insert a row with the employee data.
console.log('Inserting row with: %s', insert)
client.query(insert, next);
},
function select(next) {
// Query the row for employee id 2 and print the results to the console.
const select = 'SELECT name, age, language FROM employee WHERE id = 2;';
client.query(select, function (err, result) {
if (err) return next(err);
var row = result.rows[0];
console.log('Query for id=2 returned: name=%s, age=%d, language=%s',
row.name, row.age, row.language);
next();
});
}
], function (err) {
if (err) {
console.error('There was an error', err.message, err.stack);
}
console.log('Shutting down');
client.end();
});
```
Run the application `QuickStartApp.js` using the following command:
```js
node QuickStartApp.js
```
You should see output similar to the following if you're using SSL:
```output
Creating table employee
Inserting row with: INSERT INTO employee (id, name, age, language) VALUES (2, 'John', 35, 'NodeJS + SSL');
Query for id=2 returned: name=John, age=35, language=NodeJS + SSL
Shutting down
```
If there is no output or you get an error, verify the parameters included in the `config` object.
## Learn more
[YugabyteDB smart drivers for YSQL](../../smart-drivers/)