Node.js 连接 MySQL 并进行数据库操作

通常在NodeJS开发中我们经常涉及到操作数据库，尤其是 MySQL ，作为应用最为广泛的开源数据库则成为我们的首选，本篇就来介绍下如何通过NodeJS来操作 MySQL 数据库。 安装MySQL模块到NodeJS中 我们需要让NodeJS支持MySQL，则需要将MySQL模块添加到系统支持库

安装 node-mysql

$ npm install mysql 

创建测试表

//数据库名 NodeSample
CREATE TABLE `NodeSample`.`MyTable` (
`id` INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`firstname` VARCHAR( 20 ) NOT NULL ,
`lastname` VARCHAR( 20 ) NOT NULL ,
`message` TEXT NOT NULL
) ENGINE = MYISAM ; 

连接数据库

var sys = require(‘sys‘); 

var Client = require(‘mysql‘).Client;
var client = new Client(); 

client.user = ‘someuser‘;
client.password = ‘password‘; 

client.connect(function(error, results) {
if(error) {
console.log(‘Connection Error: ‘ + error.message);
return;
}
console.log(‘Connected to MySQL‘);
});

打开数据库

ClientConnectionReady = function(client)
{
client.query(‘USE NodeSample‘, function(error, results) {
if(error) {
console.log(‘ClientConnectionReady Error: ‘ + error.message);
client.end();
return;
}
});
};

完成数据库操作程序

var sys = require(‘sys‘); 

var Client = require(‘mysql‘).Client;
var client = new Client(); 

client.user = ‘someuser‘;
client.password = ‘password‘; 

console.log(‘Connecting to MySQL...‘); 

client.connect(function(error, results) {
if(error) {
console.log(‘Connection Error: ‘ + error.message);
return;
}
console.log(‘Connected to MySQL‘);
ClientConnectionReady(client);
}); 

ClientConnectionReady = function(client)
{
client.query(‘USE NodeSample‘, function(error, results) {
if(error) {
console.log(‘ClientConnectionReady Error: ‘ + error.message);
client.end();
return;
}
ClientReady(client);
});
}; 

ClientReady = function(client)
{
var values = [‘Chad‘, ‘Lung‘, ‘Hello World‘];
client.query(‘INSERT INTO MyTable SET firstname = ?, lastname = ? , message = ?‘, values,
function(error, results) {
if(error) {
console.log("ClientReady Error: " + error.message);
client.end();
return;
}
console.log(‘Inserted: ‘ + results.affectedRows + ‘ row.‘);
console.log(‘Id inserted: ‘ + results.insertId);
}
);
GetData(client);
} 

GetData = function(client)
{
client.query(
‘SELECT * FROM MyTable‘,
function selectCb(error, results, fields) {
if (error) {
console.log(‘GetData Error: ‘ + error.message);
client.end();
return;
}
// Uncomment these if you want lots of feedback
//console.log(‘Results:‘);
//console.log(results);
//console.log(‘Field metadata:‘);
//console.log(fields);
//console.log(sys.inspect(results)); 

if(results.length > 0)
{
var firstResult = results[0];
console.log(‘First Name: ‘ + firstResult[‘firstname‘]);
console.log(‘Last Name: ‘ + firstResult[‘lastname‘]);
console.log(‘Message: ‘ + firstResult[‘message‘]);
}
}); 

client.end();
console.log(‘Connection closed‘);
};