安装mysql模块

npm install mysql

测试是否连接成功

mysql.js代码:

  var mysql      = require('mysql');  
  var connection = mysql.createConnection({  
  host     : 'localhost',  
  user     : 'root',  
  password : '123456',  
  database : 'nodejs'  
  });  

  connection.connect();  

  connection.query('SELECT 1 + 1 AS solution', function(err, rows, fields) {  
  if (err) {  
  console.log(err);  
  return;  
  };  

  console.log('The solution is: ', rows[0].solution);  
  });  

  connection.end();  

结果 : 连接成功

image

封装连接数据库代码

支持连接池,mysql.js:

  var db    = {};  
  var mysql = require('mysql');  
  var pool  = mysql.createPool({  
  connectionLimit : 10,  
  host            : 'localhost',  
  user            : 'root',  
  password        : '123456',  
  database        : 'nodejs'  
  });  

  db.query = function(sql, callback){  

  if (!sql) {  
  callback();  
  return;  
  }  
  pool.query(sql, function(err, rows, fields) {  
  if (err) {  
  console.log(err);  
  callback(err, null);  
  return;  
  };  

  callback(null, rows, fields);  
  });  
  }  
  module.exports = db;  

测试封装

dbtest.js:

  var db = require('./mysql.js');  
  var sql = 'SELECT count(*) as count from user';  
  db.query(sql, function(err, rows, fields){  
    if (err) {  
      console.log(err);  
      return;  
    }  
    console.log('用户数量 : ', rows[0].count);  
  });  

运行结果

image

数据库截图:

image