当前位置： 首页 > wzjs >正文

网站开发案例教程seo外贸网站制作

wzjs 2025/7/19 1:11:39
网站开发案例教程,seo外贸网站制作,企业网站建设技术,腾网站建设1、参考：JavaScript语言的事务管理_js 函数 事务性-CSDN博客 或者百度搜索：Nodejs控制事务， 2、实践 2.1、对于MySQL或MariaDB，你可以使用mysql或mysql2库，并结合Promise或async/await语法来控制事务。 使用 mysql2…

1、参考：JavaScript语言的事务管理_js 函数 事务性-CSDN博客

或者百度搜索：Nodejs控制事务，

2、实践

2.1、对于MySQL或MariaDB，你可以使用mysql或mysql2库，并结合Promise或async/await语法来控制事务。

使用 mysql2/promise 示例：
const mysql = require('mysql2/promise');async function runTransaction() {const connection = await mysql.createConnection({host: 'localhost',user: 'root',password: '123456',database: 'test',});try {await connection.beginTransaction();await connection.query('INSERT INTO users (name, email) VALUES (?, ?)',["heming","yyyyyy"]);await connection.query('INSERT INTO users (name, email) VALUES (?, ?)',["jackson","john2@example.com"]);await connection.commit();console.log('Transaction committed successfully.');} catch (error) {await connection.rollback();console.error('Transaction failed:', error);} finally {await connection.end();}
}runTransaction().catch(console.error);
当前表已有2条数据
第一次运行该文件时，第二个用户的email是john@example.com，违反了唯一约束，报错如下：

事务回滚，一条记录都没有插入成功。

然后把第二个用户的email改成john2@example.com，成功了，

表多了2条记录

2.2、使用Sequelize进行事务管理

以下是一个使用Sequelize在Node.js中管理事务的示例：

// 同步模型并创建用户 sequelize.sync().then(() => { createUser(); }); ```

在上面的示例中，我们创建了一个包含用户信息的简单数据库，并通过Sequelize的事务管理来确保两个用户记录的原子性。如果创建用户的过程中发生任何错误，事务将回滚，不会对数据库造成不一致的影响。

const { Sequelize, DataTypes } = require('sequelize'); 
const sequelize = new Sequelize('sqlite::memory:');const User = sequelize.define('User', { name: { type: DataTypes.STRING, allowNull: false } });async function createUser() { // 启动事务 const transaction = await sequelize.transaction();try {const user1 = await User.create({ name: 'Alice' }, { transaction });const user2 = await User.create({ name: 'Bob' }, { transaction });// 提交事务await transaction.commit();console.log("Users created:", user1, user2);} catch (error) {// 回滚事务await transaction.rollback();console.error("Error creating users:", error);}
}sequelize.sync().then(() => { createUser(); });

执行报错：

PS D:\soft\nodejs-crud-example> npm install sqlite3       
npm WARN deprecated glob@7.2.3: Glob versions prior to v9 are no longer supported
npm WARN deprecated gauge@4.0.4: This package is no longer supported.
npm WARN deprecated are-we-there-yet@3.0.1: This package is no longer supported.
npm WARN deprecated @npmcli/move-file@1.1.2: This functionality has been moved to @npmcli/fs
npm WARN deprecated inflight@1.0.6: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful.
npm WARN deprecated npmlog@6.0.2: This package is no longer supported.
npm WARN deprecated rimraf@3.0.2: Rimraf versions prior to v4 are no longer supported
npm ERR! code 1
npm ERR! path D:\soft\nodejs-crud-example\node_modules\sqlite3
npm ERR! command failed
npm ERR! command C:\Windows\system32\cmd.exe /d /s /c prebuild-install -r napi || node-gyp rebuild
npm ERR! prebuild-install warn install read ECONNRESET
npm ERR! gyp info it worked if it ends with ok
npm ERR! gyp info using node-gyp@8.4.1
npm ERR! gyp info using node@20.10.0 | win32 | x64
npm ERR! gyp ERR! find Python
npm ERR! gyp ERR! find Python Python is not set from command line or npm configuration
npm ERR! gyp ERR! find Python Python is not set from environment variable PYTHON
npm ERR! gyp ERR! find Python checking if "python3" can be used
npm ERR! gyp ERR! find Python - "python3" is not in PATH or produced an error
npm ERR! gyp ERR! find Python checking if "python" can be used
npm ERR! gyp ERR! find Python - "python" is not in PATH or produced an error
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python39\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python39\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python39\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python39\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python39-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python39-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python39-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python39-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files (x86)\Python39-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files (x86)\Python39-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python38\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python38\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python38\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python38\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python38-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python38-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python38-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python38-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files (x86)\Python38-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files (x86)\Python38-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python37\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python37\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python37\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python37\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python37-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python37-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python37-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python37-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files (x86)\Python37-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files (x86)\Python37-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python36\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python36\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python36\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python36\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Users\Administrator\AppData\Local\Programs\Python\Python36-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Users\Administrator\AppData\Local\Programs\Python\Python36-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files\Python36-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files\Python36-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if Python is C:\Program Files (x86)\Python36-32\python.exe
npm ERR! gyp ERR! find Python - "C:\Program Files (x86)\Python36-32\python.exe" could not be run
npm ERR! gyp ERR! find Python checking if the py launcher can be used to find Python 3
npm ERR! gyp ERR! find Python - "py.exe" is not in PATH or produced an error
npm ERR! gyp ERR! find Python
npm ERR! gyp ERR! find Python **********************************************************
npm ERR! gyp ERR! find Python You need to install the latest version of Python.
npm ERR! gyp ERR! find Python Node-gyp should be able to find and use Python. If not,
npm ERR! gyp ERR! find Python you can try one of the following options:
npm ERR! gyp ERR! find Python - Use the switch --python="C:\Path\To\python.exe"
npm ERR! gyp ERR! find Python   (accepted by both node-gyp and npm)
npm ERR! gyp ERR! find Python - Set the environment variable PYTHON
npm ERR! gyp ERR! find Python - Set the npm configuration variable python:
npm ERR! gyp ERR! find Python   npm config set python "C:\Path\To\python.exe"
npm ERR! gyp ERR! find Python For more information consult the documentation at:
npm ERR! gyp ERR! find Python https://github.com/nodejs/node-gyp#installation
npm ERR! gyp ERR! find Python **********************************************************
npm ERR! gyp ERR! find Python
npm ERR! gyp ERR! configure error
npm ERR! gyp ERR! stack Error: Could not find any Python installation to use
npm ERR! gyp ERR! stack     at PythonFinder.fail (D:\soft\nodejs-crud-example\node_modules\node-gyp\lib\find-python.js:330:47)
npm ERR! gyp ERR! stack     at PythonFinder.runChecks (D:\soft\nodejs-crud-example\node_modules\node-gyp\lib\find-python.js:159:21)
npm ERR! gyp ERR! stack     at PythonFinder.<anonymous> (D:\soft\nodejs-crud-example\node_modules\node-gyp\lib\find-python.js:228:18)
npm ERR! gyp ERR! stack     at PythonFinder.execFileCallback (D:\soft\nodejs-crud-example\node_modules\node-gyp\lib\find-python.js:294:16)
npm ERR! gyp ERR! stack     at exithandler (node:child_process:430:5)
npm ERR! gyp ERR! stack     at ChildProcess.errorhandler (node:child_process:442:5)
npm ERR! gyp ERR! stack     at ChildProcess.emit (node:events:514:28)
npm ERR! gyp ERR! stack     at ChildProcess._handle.onexit (node:internal/child_process:292:12)
npm ERR! gyp ERR! stack     at onErrorNT (node:internal/child_process:484:16)
npm ERR! gyp ERR! stack     at process.processTicksAndRejections (node:internal/process/task_queues:82:21)
npm ERR! gyp ERR! System Windows_NT 10.0.19045
npm ERR! gyp ERR! command "C:\\Program Files\\nodejs\\node.exe" "D:\\soft\\nodejs-crud-example\\node_modules\\node-gyp\\bin\\node-gyp.js" "rebuild"
npm ERR! gyp ERR! cwd D:\soft\nodejs-crud-example\node_modules\sqlite3
npm ERR! gyp ERR! node -v v20.10.0
npm ERR! gyp ERR! node-gyp -v v8.4.1
npm ERR! gyp ERR! not oknpm ERR! A complete log of this run can be found in: C:\Users\Administrator\AppData\Local\npm-cache\_logs\2025-04-16T05_40_43_878Z-debug-0.log
PS D:\soft\nodejs-crud-example>

http://www.dtcms.com/wzjs/5240.html

相关文章：

  • 做酒店网站的公司电商平台开发
  • 网站制作潍坊区域自媒体软文发布平台
  • 宁波网站网站建设广州网站设计
  • 不花钱的网站建设关键词排名优化软件
  • 长宁区办理营业执照地址seol英文啥意思
  • 做网站的竞品分析注册城乡规划师好考吗
  • 免费背景图片素材网站百度seo优化规则
  • 做二手车的网站ue5培训机构哪家强
  • 网站怎么做移动端谷歌应用商店下载
  • 天津建站模板源码郑州seo外包
  • 做网站的硬件成本百度点击排名收费软件
  • 做网站和视频剪辑用曲面屏上海做网站优化
  • 网站上传用什么软件做视频格式上海百度推广优化排名
  • 武汉网站整合营销联系方式长沙百度快速优化
  • 天津专业的网站建设公司单页网站制作教程
  • 沈阳黑酷做网站建设优化公司怎么样公众号推广平台
  • wordpress交易网站百度今日小说排行榜
  • 惠州建设工程质量监督站网站网络营销主要学什么
  • 长春微建站是哪个平台的常见的网络营销工具
  • 合川集团网站建设免费二级域名分发平台
  • 汉口制作网站2023年8月疫情爆发
  • 网站建设优化服务市场seo培训机构
  • 网站建设 临沂成都seo正规优化
  • 各大搜索引擎网站提交入口关键词seo是什么意思
  • 印刷网站模板下载类似火脉的推广平台
  • 用h5做的网站百度云网盘资源
  • 湖北建站出售外链
  • 自己创做网站seo推广一年要多少钱
  • 静态网站开发课程模板郑州高端网站建设
  • b站倒过来的网站谁做的青岛seo排名收费