Node.js 连接 MySQL数据库

安装指令：npm install mysql

var mysql = require("mysql");
console.log(mysql);

// 创建链接对象
var conn = mysql.createConnection({
host:'localhost',
port:3306,
user:"root",
password:'root',
database:"wh1807"
})

// 链接数据库
conn.connect((err)=>{
if(err) throw err;
console.log("数据库链接成功!")
});

var insertSql = "insert into user1807 (username,password) values (?,?)";
var insertParams = ['dazuozuo','daydayup'];
conn.query(insertSql,insertParams,(err,result)=>{
if(err) throw err;
console.log("insert ++++++++++++++++++++++++++++++++");
// response.write(result); 返回浏览器
console.log(result);
})

var selectSql = "select * from user1807 where id > ? "; // ? 需要的参数 防止SQL注入
conn.query(selectSql,2,(err,result)=>{
if(err) throw err;
console.log("select ++++++++++++++++++++++++++++++++");
// response.write(result); 返回浏览器
console.log(result);
})

var updateSql = "update user1807 set password = ? where username = ? ";
var updateParams = ['wuhan180777777','dazuozuo' ];
conn.query(updateSql,updateParams,(err,result)=>{
if(err) throw err;
console.log("update ++++++++++++++++++++++++++++++++");
// response.write(result); 返回浏览器
console.log(result);
});

var deleteSql = "delete from user1807 where username = ?";
conn.query(deleteSql,'dazuozuo',(err,result)=>{
if(err) throw err;
console.log("delete ++++++++++++++++++++++++++++++++");
// response.write(result); 返回浏览器
console.log(result);
})

// 关闭数据库
conn.end(()=>{
console.log("数据库已经关闭了....")
})

补充菜鸟教程：
（1）连接数据库
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost', //主机
user : 'root', //用户名
password : '123456', //密码
database : 'test' //数据库名
});
connection.connect();
connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) {
if (error) throw error;
console.log('The solution is: ', results[0].solution);
});
（2）查询数据
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'root',
password : '123456',
port: '3306',
database: 'test'
});
connection.connect();
var sql = 'SELECT * FROM websites';
//查
connection.query(sql,function (err, result) {
if(err){
console.log('[SELECT ERROR] - ',err.message);
return;
}

console.log('--------------------------SELECT----------------------------');
console.log(result);
console.log('------------------------------------------------------------\n\n');
});
connection.end();
（3）插入数据
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'root',
password : '123456',
port: '3306',
database: 'test'
});
connection.connect();
var addSql = 'INSERT INTO websites(Id,name,url,alexa,country) VALUES(0,?,?,?,?)';
var addSqlParams = ['菜鸟工具', 'https://c.runoob.com','23453', 'CN'];
//增
connection.query(addSql,addSqlParams,function (err, result) {
if(err){
console.log('[INSERT ERROR] - ',err.message);
return;
}
console.log('--------------------------INSERT----------------------------');
//console.log('INSERT ID:',result.insertId);
console.log('INSERT ID:',result);
console.log('-----------------------------------------------------------------\n\n');
});
connection.end();
（4）更新数据
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'root',
password : '123456',
port: '3306',
database: 'test'
});
connection.connect();
var modSql = 'UPDATE websites SET name = ?,url = ? WHERE Id = ?';
var modSqlParams = ['菜鸟移动站', 'https://m.runoob.com',6];
//改
connection.query(modSql,modSqlParams,function (err, result) {
if(err){
console.log('[UPDATE ERROR] - ',err.message);
return;
}
console.log('--------------------------UPDATE----------------------------');
console.log('UPDATE affectedRows',result.affectedRows);
console.log('-----------------------------------------------------------------\n\n');
});
connection.end();