Node.js MySQL Count() Function
Last Updated :
07 Oct, 2021
We use the COUNT() function in MySQL to count a number of rows in a column satisfying the WHERE clause.
Syntax:
COUNT([column_name])
Parameters: COUNT() function accepts a single parameter as mentioned above and described below.
- column_name: Column’s name from which we have to return the count 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: Count publishers having id greater than 5
index.js
const mysql = require( "mysql" );
let db_con = mysql.createConnection({
host: "localhost" ,
user: "root" ,
password: '' ,
database: 'gfg_db'
});
db_con.connect((err) => {
if (err) {
console.log( "Database Connection Failed !!!" , err);
return ;
}
console.log( "We are connected to gfg_db database" );
let query = "SELECT COUNT(id) AS id_count FROM publishers WHERE id > 5" ;
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.connect((err) => {
if (err) {
console.log( "Database Connection Failed !!!" , err);
return ;
}
console.log( "We are connected to gfg_db database" );
let query = "SELECT COUNT(salary) AS salary_count FROM
publishers WHERE salary BETWEEN 5000 AND 10000" ;
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:
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