Connect MySQL from Cypress in 3 Step

Step 1) Install MySQL lib in the Cypress project

$ npm install mysqljs/mysql

Step 2) Add the following to plugins/index.js

const mysql = require("mysql");
function execQuery(query, config) {
  const connection = mysql.createConnection({
    host: "your-host.com",
    user: "username",
    password: "password",
    database: "dbname"
  });
  connection.connect();
  return new Promise((resolve, reject) => {
    connection.query(query, (error, results) => {
      if (error) { 
        reject(error);
      } else {
        return resolve(results);
      }
    });
    connection.end();
  });
}

module.exports = (on, config) => {
  on("task", {
    queryDB: query => {
      return execQuery(query, config);
    }
  });
};

Step 3) Create your spect.js

describe('DB Unit Test', function() {
    it('Test DB Connection', function() {
        cy.task(
            "queryDB",
            `SELECT '1'`
        ).then(response => {
            console.debug('DB Connection result: ', response)
        });
    })
})