一、环境配置
1.在 node.js
中安装 MySQL
npm install MySQL
2.在 node.js
中引入 MySQL
模块
MySQL = require(‘MySQL’)
3.详细代码
var express = require('express');
var mysql = require('mysql');
var router = express.Router();
router.get('/', function (req, res) {
//sql语句
var sql = `SELECT * FROM test.book_type;`;
var obj = {};
//1.创建连接
var conn = mysql.createConnection({
host: 'localhost',
user: 'root',
password: 'root',
database: 'test.book_type'
});
//2.建立连接
conn.connect();
//3.访问数据库
conn.query(sql, function (err, result) {
if (!err) {
// console.log(result);
} else {
console.log('访问数据库出错:', err.message);
}
res.send(JSON.stringify(result));
});
//4.关闭数据库连接
conn.end();
});
module.exports = router;
4.常用 SQL
语句
--添加数据
insert into user (name,age,address) values ('小兔',20,'草原');
--查询表
SELECT * FROM test.user;
--查询数据
select * from user where id=3;
select name from user where id=3;
select name from user;
--修改数据
update user set age=35 where id=2;
--逆序
select * from user order by id DESC;
--查询指定数量
select * from user limit 2;
--高级查询
select * from user where age<20;
select * from user where name like '晓%';
/* 删除数据 */
delete from student where id=8;
delete from student where id=11;
/*插入数据*/
insert into student (name,age,addr) values ('张三',20,'花都');