const mysql = require('mysql2');
const connection = mysql.createConnection({
    host     : 'localhost',
    user     : 'root',
    password : 'Skyinno251,',
    database : 'appserver'
});

connection.connect((err) => {
    if (err) {
        console.error('连接失败: ' + err.stack);
        return;
    }
    console.log('连接成功，线程ID: ' + connection.threadId);
    //
    var  sql = 'SELECT * FROM temperature where id < 50';
    //查
    connection.query(sql,function (err, result) {
        if(err){
            console.log('[SELECT ERROR] - ',err.message);
            connection.end();
            return;
        }

        console.log('--------------------------SELECT----------------------------');
        console.log(result);
        console.log('------------------------------------------------------------\n\n');
        connection.end();
    });
});