const mysql = require("mysql2/promise") let pool; const connect = async () => { if (!pool) { pool = mysql.createPool({ host: "localhost", user: "root", password: "123456", database: "express_db" }) } console.log("database is connect"); return pool; } module.exports = { connect, query: async (sql, values) => { const pool = await connect(); return pool.query(sql, values); } }