为什么node.js的Mysql Native驱动程序的查询执行时间如此之高？任何替代品？

为什么使用Mysql本机驱动程序为Nodejs执行相同的查询需要大约300毫秒,即使使用或不使用“创建池”选项？

请参阅下面附带截图中的突出显示部分

同样对于本机驱动程序执行时间,请参见下面附带的屏幕截

node.js的代码库Mysql Native驱动程序

db.js

var mysql = require('mysql');
var connectionpool = mysql.createPool({
    connectionLimit: 100, //important
    host: 'localhost',
    user: config.development.username,
    password: config.development.password,
    database: config.development.database,
    multipleStatements: true,
});

    exports.getConnection = function(callback) {
        connectionpool.getConnection(callback);
    };

emp.js

var connections = require('../config/db');
     var pre_query = new Date().getTime();
        var sqlstatements = "select  * from employees where recordstate<>'raw'and  DATE(createdAt) " + "between ('1982-03-24') and ('2017-04-23')    order by employeesID desc limit 20 offset 0;" + "select COUNT(*) as count   from employees where recordstate<>'raw'and  " + "DATE(createdAt) between ('1982-03-24') and ('2017-04-23')    order by employeesID desc";
        connections.getConnection(function(err, c) {
            console.log(sqlstatements)
            c.query(sqlstatements, function(err, projects) {


                console.log(err);
                if (!err) {
                    c.release();

                    var red = new Object();
                    red.rows = JSON.parse(JSON.stringify(projects[0]));
                    red.count = JSON.parse(JSON.stringify(projects[1]))[0].count;
                    var post_query = new Date().getTime();
                    // calculate the duration in seconds
                    var duration = (post_query - pre_query) / 1000;
                    console.log(duration)
                        // console.log(red);
                    res.json(red);

                }
            })
        })

解决方法:

您在JS中的测量包括连接设置和结果的所有处理. MySQL Workbench(和MySQL终端客户端)中报告的时间只是服务器报告的内容(运行查询和结果传输).连接设置可能需要300ms的大部分时间.尝试在运行实际查询之前将pre_query init移动到该行.并在此之后直接结束时间测量(在console.log(错误)调用之前.这提供了与其他客户端工具报告的结果相当的结果.

标签：mysql,node-js,mysql-workbench,node-mysql
来源： https://codeday.me/bug/20190705/1391688.html