【发布时间】：2021-09-26 14:22:04
【问题描述】：
当我尝试在 NodeJS 中更新 MySQL 记录时，我在 Visual Studio Code 的终端中收到“应用程序崩溃”错误。
app2.js：
const express = require('express');
const mysql = require('mysql');
// create connection
const db = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'journey_test'
})
// connect to mysql
db.connect(err => {
if(err) {
throw err
}
console.log('MySQL Connected');
})
const app = express()
app.use(express.static('public'));
app.set('view engine', 'ejs');
// this pulls index.ejs to the root folder location of the site
app.get('/', function (req, res) {
res.render('index2');
});
app.post('/change/:artist/:id', (req, res) => {
let newArtist = req.params.artist;
let newID = req.params.id ;
// even hard-setting variables in my query causes failure
let sql = `UPDATE tblbillboardcomplete SET artist = 'The Cure' WHERE id = '104'`
let query = db.query(sql, err => {
if(err) {
throw err
}
res.send('Entry updated');
})
})
app.listen('3000', () => {
console.log('Server Started on port 3000')
})index2.ejs：
<!DOCTYPE html>
<html>
<head>
<script>
function testing() {
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
const text = this.responseText;
const obj = JSON.parse(text);
document.getElementById("Hello2").innerHTML = "Yes!";
};
xhttp.open("POST", "change/The Cure/104", true);
xhttp.send();
}
</script>
</head>
<body>
<button style= "height:22px";" type="button" onclick="testing()">Update</button>
<div id="Hello2">Did I do it?</div>
</body>
</html>Powershell 中的错误：
PS C:\Users\Mervius\Documents\NodeJS> nodemon app2.js
[nodemon] 2.0.12
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: js,mjs,json
[nodemon] starting `node app2.js`
Server Started on port 3000
MySQL Connected
C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Parser.js:437
throw err; // Rethrow non-MySQL errors
^
Error: ER_PARSE_ERROR: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UPDATE tblbillboardcomplete SET artist = 'The Cure' WHERE id = '104'' at line 1
at Query.Sequence._packetToError (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\sequences\Sequence.js:47:14)
at Query.ErrorPacket (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\sequences\Query.js:79:18)
at Protocol._parsePacket (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Protocol.js:291:23)
at Parser._parsePacket (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Parser.js:433:10)
at Parser.write (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Parser.js:43:10)
at Protocol.write (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Protocol.js:38:16)
at Socket.<anonymous> (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\Connection.js:88:28)
at Socket.<anonymous> (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\Connection.js:526:10)
at Socket.emit (events.js:375:28)
at addChunk (internal/streams/readable.js:290:12)
--------------------
at Protocol._enqueue (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\protocol\Protocol.js:144:48)
at Connection.query (C:\Users\Mervius\Documents\NodeJS\node_modules\mysql\lib\Connection.js:198:25)
at C:\Users\Mervius\Documents\NodeJS\app2.js:36:24
at Layer.handle [as handle_request] (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\layer.js:95:5)
at next (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\route.js:137:13)
at Route.dispatch (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\route.js:112:3)
at Layer.handle [as handle_request] (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\layer.js:95:5)
at C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\index.js:281:22
at param (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\index.js:354:14)
at param (C:\Users\Mervius\Documents\NodeJS\node_modules\express\lib\router\index.js:365:14) {
code: 'ER_PARSE_ERROR',
errno: 1064,
sqlMessage: "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UPDATE tblbillboardcomplete SET artist = 'The Cure' WHERE id = '104'' at line 1",
sqlState: '42000',
index: 0,
sql: "UPDATE tblbillboardcomplete SET artist = 'The Cure' WHERE id = '104'"
}
[nodemon] app crashed - waiting for file changes before starting...在 MySQL 控制台中工作的查询： You can see it works.
使用 WAMP 服务器（因为我将以前的 Visual Basic WinForms 应用程序重新构建为 Web 应用程序）： MySQL：5.7.9 阿帕奇：2.4.17
我发誓上述方法几天前才有效，但当时环境可能发生了一些变化（例如安装更多节点模块，诸如此类，尽管当时我肯定使用的是 WAMP 服务器）。
任何帮助表示赞赏。
编辑：我在使用 NodeJS 选择或插入 MySQL 数据库时没有遇到任何问题。
添加（在 John Michael Manlupig 的建议最初奏效之后，至少在原始上下文中）： 问题在另一个地方仍然存在。我通过 tinymce 富文本编辑器将信息（作为“结果”）发布到 app.js，但在使用以下代码时以同样的方式失败：
const express = require('express');
const mysql = require('mysql');
//const dayjs = require('dayjs');
const multer = require('multer');
const upload = multer({ dest: 'uploads/' });
app.post('/result', upload.none(), function (req, res, next) { // when we save RTE info in tinymce
var newEntry = req.body.content
var newDate = activedate
const sql = `UPDATE main SET entry = ? WHERE dateID = ?`;
const query = db.query(sql, [newEntry, newDate], err => {
if(err) {
throw err
}
res.send('Entry updated');
})
});我可以将接收到的“req.body.content”值发送到控制台，这很好，但是通过其余代码发送它会导致“应用程序崩溃”的方式与上述相同，尽管参数化为由@John Michael Manlupig 建议，尽管查询文本包含正确/预期的信息，并且可以在 MySQL 控制台中按原样使用。
有什么明显的我忽略了吗？
【问题讨论】：
标签： javascript mysql node.js express