创建并连接数据库，并修改登录和注册接口

db/mysql.js

@@ -0,0 +1,20 @@
+const mysql = require('mysql2')
+
+const connection = mysql.createConnection({
+  host: 'localhost',
+  port: 3306,
+  user: 'root',
+  password: '960707Shf_',
+  database: 'chat_mysql'
+})
+
+connection.connect((error) => {
+  if (error) {
+    console.error('MySQL 连接失败：', error)
+    return
+  }
+
+  console.log('MySQL 连接成功！')
+})
+
+module.exports = connection