Work with databases (DB)

//SQLite example
//using Node.js
//npm install sqlite3

// Connect to the database
const sqlite3 = require('sqlite3');
let db = new sqlite3.Database('DatabaseName.db', (err) => {
    if (err) {
        return console.error(err);
    }
});

let sql = `
    SELECT
        Language, Percentage
    FROM countrylanguage
    WHERE CountryCode = 'RUS'
    ORDER BY Percentage DESC`;

db.serialize(() => {
    // SQL query execution
    db.each(sql, (err, row) => {
        if (err) {
            return console.error(err);
        }
        console.log(row.Language + ": " + 
            row.Percentage);
    });
});  
db.close();