javascript - 从 ejs 文件连接到 mysql

Question

我是 node.js 的新手，正在尝试学习如何从 ejs 文件连接到 mysql 数据库。我试图搜索示例代码，但该代码无法正常工作。有人可以帮我检查一下吗？谢谢。

function loaddata() {

          var sql = require("mysql");
          var con = mysql.createConnection({});
          con.connect(function (err) {
              if (err) {
                  console.log('Error connecting to Db');
                  return;
              }
              console.log('Connection established');
          });
          con.query('update students set name="sus" where email="smn14@mail.aub.edu"', function (err, rows) {
              if (err) throw err;

              console.log('Data received from Db:\n');
              console.log(rows);
          });
          con.end(function (err) {
              // The connection is terminated gracefully
              // Ensures all previously enqueued queries are still
              // before sending a COM_QUIT packet to the MySQL server.
          });


      }

Answer 1

创建连接最差。

 var mysql      = require('mysql'); 
 var connection = mysql.createConnection({   
     host : 'localhost',
     user : 'me', 
     password : 'secret',   
     database : 'my_db' 
 });     
 connection.connect();     
 connection.query('SELECT 1 + 1 AS solution', function(err, rows,
 fields) {   
     if (err) throw err;     
     console.log('The solution is: ', rows[0].solution); });     
 connection.end();

---

From this example, you can learn the following:

Every method you invoke on a connection is queued and executed in sequence.
Closing the connection is done using end() which makes sure all remaining queries are executed before sending a quit packet to the

mysql server.

Docs