Node.js MySQL AVG() Function
We use AVG Function to get the average value of all rows in the given column of MySQL Table.
Syntax:
AVG([column_name])
Parameters: AVG() function accepts a single parameter as mentioned above and described below.
- column_name: Column’s name from which we have to return the average value.
Module Installation: Install the mysql module using the following command.
npm install mysql
Database: Our SQL publishers table preview with sample data is shown below:
Example 1:
index.js
const mysql = require( "mysql" ); let db_con = mysql.createConnection({ host: "localhost" , user: "root" , password: '' , database: 'gfg_db' }); db_con.on( 'error' , (err) => { console.log(err.code); }); db_con.connect((err) => { if (err) { console.log( "Database Connection Failed !!!" , err.code); return ; } console.log( "We are connected to gfg_db database" ); // Here is the query let query = "SELECT AVG(salary) AS avg_salary FROM publishers" ; db_con.query(query, (err, rows) => { if (err) throw err; console.log(rows); }); }); |
Run the index.js file using the following command.
node index.js
Output:
Example 2:
index.js
const mysql = require( "mysql" ); let db_con = mysql.createConnection({ host: "localhost" , user: "root" , password: '' , database: 'gfg_db' }); db_con.on( 'error' , (err) => { console.log(err.code); }); db_con.connect((err) => { if (err) { console.log( "Database Connection Failed !!!" , err.code); return ; } console.log( "We are connected to gfg_db database" ); // Here is the query let query = "SELECT AVG(salary) AS avg_salary FROM publishers WHERE id < 8" ; db_con.query(query, (err, rows) => { if (err) throw err; console.log(rows); }); }); |
Run the index.js file using the following command.
node index.js
Output: