node.js操作mysql

先暂且不涉及连接池，单纯的对数据库进行操作。node.js的封装非常漂亮，对数据库的操作，提供了统一的接口 

var mysql  = require('mysql');  

var connection = mysql.createConnection({     
  host     : 'localhost',       
  user     : 'root',              
  password : '',       
  port: '3306',                   
  database: 'NodeSample', 
}); 

connection.connect();

var  userAddSql = 'INSERT INTO MyTable(firstname, lastname, message) VALUES(?,?,?)';
var  userAddSql_Params = ['James', 'Potter', 'hello world'];

var userModSql = 'UPDATE MyTable SET firstname = ?,lastname = ?, message=? WHERE Id = ?';
var userModSql_Params = ['Petter', 'HK', 'modify this' , 5];

var  userDelSql = 'DELETE FROM MyTable WHERE Id=?';
var userDelSql_Params = [5];


connection.query(userDelSql, userDelSql_Params,function (err, result) {
        if(err){
         console.log('[ERROR] - ',err.message);
         return;
        }        

       console.log('-------------------------------------------------------------');
       //console.log('INSERT ID:',result.insertId);        
       console.log(result);        
       console.log('-------------------------------------------------------------');  
});

connection.end();

var mysql  = require('mysql');  

var connection = mysql.createConnection({     
  host     : 'localhost',       
  user     : 'root',              
  password : '',       
  port: '3306',                   
  database: 'NodeSample', 
}); 

connection.connect();

var  userGetSql = 'SELECT * FROM MyTable';
var  userDelSql = 'DELETE FROM MyTable';


connection.query(userGetSql, [],function (err, result) {
        if(err){
          console.log('[SELECT ERROR] - ',err.message);
          return;
        }        

       console.log('--------------------------SELECT----------------------------');
       console.log(result);        
       console.log('-----------------------------------------------------------------');  
});

connection.end();

下面使用连接池查询数据库

// Create a MySQL connection pool with
// a max of 10 connections, a min of 2, and a 30 second max idle time
var Pool = require('generic-pool').Pool;
var mysql = require('mysql'); // v2.10.x

var pool = new Pool({
    name     : 'mysql',
    create   : function(callback) {
        var c = mysql.createConnection({
                user: 'root',
                password: '',
                database:'NodeSample'
        })

        // parameter order: err, resource
        callback(null, c);
    },
    destroy  : function(client) { client.end(); },
    max      : 10,
    // optional. if you set this, make sure to drain() (see step 3)
    min      : 2,
    // specifies how long a resource can stay idle in pool before being removed
    idleTimeoutMillis : 30000,
     // if true, logs via console.log - can also be a function
    log : true
});

// acquire connection - callback function is called
// once a resource becomes available
pool.acquire(function(err, client) {
    if (err) {
        // handle error - this is generally the err from your
        // factory.create function
    }
    else {
        client.query("select * from MyTable", [], function(err, result) {
            console.log('-------------------------------------------------------------'); 
            console.log(result);
            console.log('-------------------------------------------------------------');  

            // return object back to pool
            pool.release(client);
        });
    }
});

// Only call this once in your application -- at the point you want
// to shutdown and stop using this pool.
pool.drain(function() {
    pool.destroyAllNow();
});